How Artificial Light Is Wrecking Your Sleep, and What to Do about It | Chris Kresser
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How Artificial Light Is Wrecking Your Sleep, and What to Do about It

by Chris Kresser

Last updated on

“A good laugh and a long sleep are the best cures in the doctor’s book.” – Irish Proverb

The evidence for the health benefits of adequate, restful sleep is overwhelming. Decades of research has shown that sleeping between 7 and 9 hours per night can relieve stress, reduce the risk of many chronic diseases, improve memory and cognitive function, and may even help with weight loss. (1) As many of us know by now, getting adequate, high-quality sleep is one of the most important, yet under-appreciated steps you can take to improve your overall health and well-being.

Yet for all we know about the benefits of sleep, there are millions of Americans who are still suffering from disordered sleep and insomnia. More than one-third of Americans report getting less than 7 hours of sleep per night, and 63 percent of Americans say their sleep needs are not being met during the week. (2, 3) The negative effects of sleep deprivation are serious: sleep durations that are consistently shorter than 7 hours in a 24-hour period are associated with cardiovascular disease and diabetes risk factors, depression, automobile and workplace accidents, learning and memory problems, and an overall increase in mortality. (4) Some may argue that poor sleep can even undo the benefits of a healthy diet and exercise routine. (5, 6)

Could using electronics at night ruin your sleep and increase your risk of death and disease? Check out this article to find out. #healthylifestyle #wellness #chriskresser

So what’s causing this epidemic of sleep disruption in our country? Many experts feel that our excessive use of communications technology (e.g. cell phones, laptops, television, etc.) is driving this significant level of sleep deprivation. If this is the case, it’s no wonder so many Americans struggle with poor sleep, since 95 percent have reported using some type of electronics at least a few nights a week within the hour before bed. (7) Checking email, watching your favorite late-night comedian, or responding to a text message in bed seems harmless enough, but the sleep disruption caused by these light-emitting devices is significant and potentially harmful to your health.

Research has demonstrated that nighttime light exposure suppresses the production of melatonin, the major hormone secreted by the pineal gland that controls sleep and wake cycles. (8) Therefore, a reduction in melatonin at night is associated with subjective levels of sleeplessness. (9, 10) But melatonin suppression has far worse consequences than simply poor sleep outcomes: it has also been shown to increase the risk of cancer, impair immune system function, and possibly lead to cardiometabolic consequences such as type 2 diabetes, metabolic syndrome, obesity, and heart disease. (11, 12, 13)

With serious consequences like these, preventing melatonin suppression should be a top priority in anyone’s healthy lifestyle.

Blue Light and Melatonin Suppression

It is well established that short-wavelength or “blue” light is the most melatonin-suppressive; this is the type of light typically emitted by devices such as televisions, computer screens, and cellphones. (14, 15) To produce white light, these electronic devices must emit light at short wavelengths, close to the peak sensitivity of melatonin suppression. (16) This means that products such as tablets, smartphones, and other devices with self-luminous electronic displays are major sources for suppressing melatonin at night, thereby reducing sleep duration and disrupting sleep. (Figure credit: Wood et al, 2013)

Melatonin graph

Along with blue light emitted from electronic devices, research has shown that being exposed to normal levels of room lighting can have similar negative effects on melatonin. One study showed that one hour of moderately bright light exposure (1000 lux) was sufficient to suppress nocturnal melatonin to daytime levels. (17) Since melatonin suppression is intensity dependent, researchers suggest that lower intensities can have similar suppression effects at longer durations; for example, two hours at 500 lux would have a similar effect as one hour at 1000 lux. (For examples of lux values, check out this helpful chart.) This means that typical room light alone can have a similar suppressing effect on melatonin secretion as the light from backlit screens. (18)

How to Prevent Melatonin Disruption (Without Tossing Your iPhone)

Since it is predominantly the blue wavelength that is most affective in melatonin suppression, it stands to reason that blocking this wavelength of light should be enough to significantly reduce, or even eliminate the melatonin-suppressing effects of nighttime light exposure. (19) In fact, blocking blue light has been shown in several studies to be extremely effective in reducing the melatonin-suppressing effects of intense and/or blue light. (20, 21)

There are a few possible solutions for reducing your exposure to blue light at night. One that is commonly used in the ancestral health community is f.lux, a program that makes the color of your computer’s display adapt to the time of day, warm at night and like sunlight during the day. This program can be installed on computers, iPads, and iPhones, and may have a significant effect on your melatonin secretion when using these devices at night. The best part about this program is that it turns on automatically in response to the daylight in your particular time zone, so there’s no need to remember any adjustments to the screen.

A better option, in my opinion, is to use amber-lensed goggles once the sun has gone down. These blue-blocking lenses are highly effective in reducing the effects of blue light exposure, and in most cases completely eliminate the short-wavelength radiation necessary for nocturnal melatonin suppression. (22, 23, 24) These goggles have been shown to improve sleep quality as well as mood, simply by blocking blue light and simulating physiologic darkness.

The main reason I recommend using these goggles is because normal room light alone is enough to suppress melatonin at night, and unless you’re shutting off all the lights in your house when the sun sets, you’re still at risk for disrupting your melatonin-driven circadian rhythms. (25) While f.lux is a useful tool for your backlit devices, it’s nearly impossible to address all sources of melatonin-suppressing light in today’s world of modern technology and late-night work and entertainment habits. Amber-colored goggles are one of the only tools available to completely eliminate all blue light exposure at night, without ‘going off the grid’ and powering down your entire house after 7 PM.

There are two excellent (and cheap!) options for amber-lensed goggles on Amazon. The cheapest and most popular option is the Uvex brand, but if you wear eyeglasses you’ll need to get a wraparound pair like the Solar Shield brand. I’ve had many patients swear by these goggles, and if you can get over the dorkiness factor, you may find they make a big difference in your sleep quality, and perhaps even your general health and wellbeing as well!

Have you ever used amber-lensed goggles, or f.lux, to improve your sleep quality? Share your experience in the comments below.


Join the conversation

  1. Our city has installed LED streetlights and in my neighborhood, my house on the corner has three lights very close. On some nights when it is cloudy or a new moon, I will wake up in the middle of the night and it feels like daylight in my room, hallway, living room and kitchen. I wonder if there are shades that a specific to blue light? Aside from wanting to make the case to the council, that would be my next best solutiuon.

    • Erin, that would be a great idea for window coverings and I hope you find some. That said, I know from experience that if you don’t cover your windows (at least your bedroom window) thoroughly, the light that gets in the cracks at the side seem like laser beams. 😉 I spent so much time trying to find a light proof solution for the bedroom window until I simply decided to cover it completely. My sleep has improved by leaps and bounds, especially as I only use my room for sleep; no reading and definitely no t.v. or phones. P.S. I bought some red blue-blockers from somnilight and they work much better than my amber blue blockers for t.v at night. Often I’ll also put them on to go to the bathroom in the middle of the night so that I can fall asleep again much faster.

  2. Since we are finding out that our bodies are far more whole and not segmented into different parts than we realized in times past, is the blue light issue also pertinent to our skin absorbing this? I’m wondering because I bought the blue-blocker glasses to wear in the evenings but the change is minimal.
    I have insomnia so end up falling asleep with a DVD on which goes to blue screen because the movie ends. I even sleep with the blue-blocker glasses on so that the TV light won’t affect me and for trips to the bathroom in the middle of the night.
    If skin can absorb this blue light then those of us who share my situation have further issues if we aren’t sleeping in black-out rooms. Yes, I’ve tried turning off the TV for several months at a time and insomnia got much worse. Can’t turn off mind!
    Can’t find any articles addressing the skin absorbing light question. Our skin absorbs a lot of things, maybe even this blue light. Anyone know about this?

    • Nancy, I just asked that very question yesterday on another site. It does emit the blue light, but some ppl will say that it’s not pointed directly at your eyes, so it’s not as bad. Apparently, the original Kindle e-ink didn’t have a light source, but not 100% sure. All I know is that when I read that they still emit blue light, I couldn’t personally take a chance. You can lower the light, though, so if you’re eyes aren’t as sensitive to light as mine, you may be able to get away with wearing blue blocker glasses while reading..

  3. Dear Chris,
    I am thinking that it would be good for us to use blue light at morning time. When we pass midday orange light could progressively added at evening time.

    What is your opinion?

  4. Hey Chris,

    Awesome post! I’ve been using f.lux for awhile but I feel like now I’m almost immune to it – is that a possibility or am I just being dramatic? I also use the function on the iphone to make it a bit darker @ night which helps when I’m in the bed and still want to read an article (like yours…haha).

    • I don’t think you’re being dramatic; I’ve found that I can’t read on my pc or phone after dark no matter what. I have f.lux on the lowest setting (1200 incandescent), plus I wear blue blockers and I find it far too bright. I did find their ‘darkroom’ feature and that’s a lot better, but within a short time, it also becomes too bright–my eyes adjust, I guess, and it becomes intolerable.

  5. Chris, I use the f.lux app on all of my devices and its helped a ton! I feel like the next step I need to take is to turn off all of the other artificial light that is in my house that keeps me feeling like its daylight when in reality its night time. I’m going to start my nighttime yoga practice with the lights off using f.lux and see if that allows me to more easily get to sleep.

  6. Chris, this is an important post, and perhaps the most well-informed comments section I’ve seen! I too, use f.lux (and Twilight on android) every night, and it certainly makes a huge difference. Even so, I’ve found that the best thing at night is using native amber LEDs, which emit essentially no blue or green wavelengths to begin with (single color LEDs, like lasers, emit only a very narrow band of amber light).

    After my favorite amber book light broke (and went entirely out of production), I actually started a whole company to start producing amber book lights myself. That’s dedication to an accessory. Anyway, though you might be interested in an amber desk lamp or book lamp, which are available here: I find it’s more comfortable than wearing blue-blocking glasses at night.

    Under “Research” I’ve also collected all of the latest research on blue light, melatonin production, and health. It’s some fascinating stuff! Anyway, thought you might find it interesting!


    • I just ordered from your page last week (the amber desk lamp for reading and the red blue blockers) and am anxious to start using them. Funny thing is, I didn’t make the connection between your post here and finding the somnilight site when I searched for ‘red blue-blockers’. Small world…

  7. Two questions

    1. I use amber Uvex goggles. I don’t go to sleep until ~midnight, which is 6 hours after the sun sets. Should I wear orange goggles for the entire 6 hours (currently, I wear them for 2 hours before)

    2. Using goggles with lights/electronic devices is better than not, but is avoiding lights all together the best option? (i.e., blocking blue light is good, but blocking all light is better)?

  8. Can f.lux be updloaded/downloaded onto a new 2015 LED Smart TV?? Ever since we purchased our TV, my husband and I both notice a decrease in sleep and it is driving us crazy!

    • Hey Jennifer,

      I have an Samsung LED Smart TV, and it’s possible to change the color on it to red. I went to the advanced settings and did this. This basically does what f.lux does.

      I’d also recommend wearing the blue light glasses Chris Kresser recommends and switching to red or amber lightbulbs. I tried both of the glasses recommended on this site and I liked the Uvex pair better; it’s very hard to see with the other pair on.

  9. I would definitely recommend downloading f.lux. It’s free, it took my computer less than 30 seconds to download, and it’s worked wonders for my insomnia I was suffering from for a while. I like to watch Netflix to help me sleep at night, and with no blue light, I still feel tired, as opposed to feeling more awake, and having eye strain like before. A+ for f.lux!

  10. Hi, all. I work under the usual ugly florescent lights in my office. I can see windows in the distance but not much natural light hits me during the day. Would appreciate any recommendations for how to simulate daylight in my office.

    • I don’t know if you carry any weight where you work but you might be able to sweettalk the maintenance man into installing daylight frequency fluorescent bulbs in the fixtures near your desk

  11. Awesome app for the computer! Wish I didn’t have to jailbreak my phone ):
    Be wary of the glasses that fully block out blue rays… If you’re working on a computer you may want to use “Blutech” lenses ONLY while using the computer as blue light also effects your mood cycle. There’s also another lens called Provencia that blocks enough to help with your mood cycle just doesn’t mess with your mood cycle. Not enough blue light can lead to depression and crankiness!!

    • Clarification needed here. Without a doubt, unless you’re working the night shift and need to stay alert at night, you want to block out 100% of the blue light at NIGHT. Yes, a daily dose of blue light is essential for our health, however, we should get it during the daytime… especially the morning time. Have breakfast in a sunny room, if possible, go out for a walk at 10:00 A.M. Research shows that getting a daily dose of blue light during the daytime, dramatically increases our body’s ability to produce essential and increased levels of melatonin at night.

      • Clarification needed under your comment. Blue ligh is needed when you start your circadian rhytm and trought your circadian activity, “daily dose of blue light during the daytime,” you dont need study only logic o know that if blue light is major factor in melatonin then is logical that we need exposure to regulate this hormon.

        • I’m working with a sleep specialist and this is the opinion of only one doctor. “Morning” refers to YOUR morning. “Daytime” refers to YOUR daytime. My day starts later than others and I crave sunlight because I don’t get enough natural light. I get some though. Artificial broad-spectrum light can help but I really feel sorry for all the people who work night shift. Like I said this is MY doctor’s opinion. Other people may have different ones. He also showed me why my sleep seems random – according to what he knows, cutting off the melatonin cycle doesn’t reset it, it just pauses it. We’re still confirming I have DSPD and not a non-24 rhythm.

          • “He also showed me why my sleep seems random – according to what he knows, cutting off the melatonin cycle doesn’t reset it, it just pauses it. We’re still confirming I have DSPD and not a non-24 rhythm.” pls start using brain, melatonin is regulated by light not any internal clock, internal clock is regulated by melatonin secretion, you cannot pause melatonin or reset etc. and there is no such thing like melatonin cycle its a hormon which respond to internal stimuls.

            • Darius
              Melatonin has its own endogenous rhythm and is not only affected by light but also time of day.
              You may wish to engage your own brain and do a little research before posting such harsh comments to someone who is obviously struggling circadian issues and is under the care of a sleep expert.

      • You bring up a couple good points, and there may be one hiding in between. Suppressing melatonin production commonly extends circadian rhythm, and shortening that rhythm needs other magic. The melatonin can only be suppressed when the circadian cycle is trying to produce it, so that permits plenty of good ole daylight.
        Circadian disruption is directly connected with several health issues, and the melatonin is connected with reducing breast cancer. The late night workers needing periodic nap time, while work time is beneath the cool-white lighting are subject to the cancer increases, not to mention circadian upset.
        A trial to feel better during circadian upset may be to overcome “Jet Lag” with 3 or more time zones. Fly East Coast to West Coast, then wish to sleep when no one else does. West to East flight has you watching the solid state TV which suppresses natural melatonin production when it finally tries..
        Tinted glasses one way, wine the other.

    • There’s also the Twilight app on Android. Not sure about other platforms. Works the same way. It’s pretty awesome.

    • Stephanie- could you elaborate a little or send me to an article where they go in depth on blocking and mood interference? I found that after wearing my UVEX glasses in the evening, when I went to bed, I was very anxious to the point of a panic attack. All I had done differently was wear those goggles so I’m intrigued if these could be related? Any literature or comments are appreciated!

  12. Another way to filter out blue light is to invest in a blue-light filtering eyeglass lens. FL-41 tint has been proven to filter out this type of light. Google it.

  13. I downloaded the f.lux app for my macbook and noticed the yellow tint to the screen that night, but never gave it a second thought. That night I slept the best I had in months. But I didn’t make the connection. I thought perhaps I had had plenty of fresh air that day. lol. The second night I also slept very well– straight through six hours instead of waking up after three hours as usual. Now I can’t deny the correlation between the app and my sleep. I just ordered a pair of the blue-blocking glasses to help me when I’m reading my phone and watching tv in bed too as I am totally convinced of the need to reduce blue light at night.

  14. Can you point me to the “Research has demonstrated that nighttime light exposure suppresses the production of melatonin”. my wife doesnt believe me on this and lets our daughter have multiple lights on a night.


  15. Amber lenses work really well unfortunately for me. I work overnights in front of a screen all day and use amber lenses to reduce eye strain, but working in a dark environment this causes my melatonin levels to go up and get sleepy to early. So overnight workers be wary.

    • Try an FL-41 lens instead of a regular Amber lens, it is specifically designed to filter out the bad part of the blue light spectrum

  16. Hi Chris,

    I bought the uvex glasses but now I have a double problem because here where I like at moment the days are shorter, for example now it is getting dark at 8 pm, in 2 months time it will get dark at 10 pm and get bright at 4 am, I do not know how the glasses will help me on this case, should I use them anyway even though is still bright for some hours and when it gets dark try to go to sleep? Or what can I do on this case in order to get a good night sleep? Cheers.

    • Wearing the glasses tells your brain that the sun has set, and it is now night time. You can put them on well before sunset and they should still help. Depending on the quality of the specific glasses you have, and how much sun exposure you get, you may even need to put them on earlier to get the same effect.

      Play with it, and see what works for you.

  17. I did a cheap blue blocking screen for my pc using orange cellophane paper . I use 4 sheet for that. I tried red cellophane paper , but it doesn’t work very well. I tested using the Uvex S1933X Skyper glasses and the effect of colors on the screen
    are the same.

  18. Just a quick reminder… Whether you fall asleep or not, darkness is key to essential melatonin production– at least from the vantage point of your eyes. That is why a sleeping mask can be useful. If you can’t fall asleep, but are still quiet and comfortable in the dark, “rest assured” (pun intended 😉 that your body is still producing melatonin. The flip side of this clarification is that even though you might have slept a solid 8 hours, your body did NOT produce a healthy amount of melatonin if you slept with: a streetlight shining through your bedroom curtain, a hallway light shining into your room (unless it was a dim amber or dim red), a TV or computer screen on, etc. (unless you managed to keep your sleeping mask on throughout the night). Most of you on this forum know that lack of naturally produced melatonin may increase the risk of breast, colon, prostate, pancreatic cancers; some lymphomas; type 2 diabetes; obesity; heart disease; mental, mood, memory and sleeping disorders; interferes with the effectiveness of Tamoxifen, a breast cancer chemotherapy drug; and so much more. If you have a special interest in a particular disease, do an internet search for melatonin/ circadian disruption/ and plug in the name of the disease you are researching. Happy dreams everyone.

    • I love this information but my 17 year old son insists on proof… do you have any scientific paper links to this?

    • dozeslam, please dont spread quackery.
      “The flip side of this clarification is that even though you might have slept a solid 8 hours, your body did NOT produce a healthy amount of melatonin if you slept with: a streetlight shining through your bedroom curtain, a hallway light shining into your room (unless it was a dim amber or dim red), a TV or computer screen on, etc. (unless you managed to keep your sleeping mask on throughout the night).” most of street light have > 530 nm wavelengths and Kayumov et al. found that > 530 nm wavelengths do not supress melatonin even in bright light, also studies looking at night shift worker who were exposed to light greater than 540nm dont have lower melatonin.

      • “most of street light have > 530 nm wavelengths”

        If you mean streetlights have NO light BELOW 530nm, I think that’s completely wrong.

        Citation needed. I’ve checked a lot of sources in the past half hour and find no support for this claim at all. I wonder why you believe it and what source you rely on to say it.

        If you mean that most streetlights do have some light above 530nm, sure, that’s true. Doesn’t affect the problems caused by blue light at all.

        Possibly you’re confusing color temperature — you may be talking about “warm white” lights. Can’t blame you, that’s what my city’s light department asserted when they put in the white LED lights. Someone in the industry fooled them.

        You can look this stuff up for yourself:

          • I used to like watching the street light in front of my house turn on and warm up from red to yellow. This is the first I’ve seen sodium vapor street lights. It’s really confusing on roads with traffic lights but perfect for a residential neighborhood. I’m old enough that I’m guessing a lot of Americans have never seen them and the suburbs here make the city I lived in a suburb of look rural… And I’ve lived in places where I’ve helped neighbors catch a goat that escaped from one person’s yard. It took moving to a city to see these. Street lights have always been blue to me.

            That didn’t last long. When a delivery truck knocked over that light, we got a blue LED one. Gone are those relaxing evenings. The only thing that keeps it out is a few layers of black lawncare garbage bags. The thing makes my ears ring. The main roads are one thing but what is the reason residential streets need to be bright as day when the sun sets? There are more popping up. I don’t know where I saw it but I was looking at LED vs fluorescent and some of the white ones aren’t allowed near playgrounds they emit so much UV. I’ve seen some of the white ones and that would be even worse. Really, I have to wonder if this is natural selection getting rid of us…

            Be careful around those new lights you were cursed with – they’re so bad for you. May as well start wearing sunscreen and eye protection at night now.

            So long and thanks for all the fisj

            • “I saw it but I was looking at LED vs fluorescent and some of the white ones aren’t allowed near playgrounds they emit so much UV.” pls check what st…y you wrote fluorescent dont emit so much blue light(check studies which looking at this issue) second led emit virtualy 0 UV

  19. Subject: Circadian Rhythm Puzzle Pieces

    Currently this blog has many reports of Circadian improvements by clean light. Circadian is a direct connection to Melatonin, for which our world has several lab tests. Our AMA has a policy for this lighting issue, and we have lab tests showing specifically that Melatonin helps prevent breast cancer and more.

    That Circadian label is an opening. Health Insurance handles things by gambling and billing. They question your packs of cigs a week, or maybe cigar usage. Obama Care can charge up to 50% more for smokers, maybe that is based on your decades.

    Are you that night time employee and do you know the lighting sprayed?

    Do we need a devoted web blog?

  20. Yes, bought the blue-blocking goggles from Dr. Richard Hanslser of So far, yes, they have helped quite a bit, too pricey though.

  21. Do all amber glasses block blue light? Or do they have to be specially made? IOW, is the color of the lenses the key, or is there something else special to take into consideration? I wear safety glasses out in the sunlight when I do yard work, because polycarbonate lenses protect from UVA and B. They cost about $7 at WalMart, and they’re in the sports department (for shooting). They also come in amber/yellow, and I’m wondering if buying them in that color and wearing them in the evenings would block blue light?

    • Whitney,

      It’s not just the color. There is a certain type of lens tint that is made to filter Near UV-A blue light. The amber color itself is best for computer screens but you can get brown or grey that block blue light too.

      We also offer a lens with an anti-reflective coating made to filter Near UV-A and it has no tint at all. Both of the lens types we offer are polycarbonate which filters UV-A and UV-B.

      They are available as reading glasses or without magnification.

    • Yes, the $7 polycarbonate yellow/amber safety glasses work. Polycarbonate blocks ultraviolet; the yellow/amber tint blocks the blue light.

      These come in “light, medium, dark” tints — if the lightest tint doesn’t help you sleep, turn down or off the white lights!

      You can also find “NoIR” brand if you want to pay more.

      And try the Rosco theatrical/photography color film over the TV/computer/phone screen; that costs $7 for a 22×24″ piece at any good theatrical or photo store. “Roscolux #23 Orange” blocks a lot of the blue:

      #19 “Fire” blocks it all:

      #22 “Deep Amber” is close:

      • I have DSPD and need verified blue light blocking glasses. I’ve been working with the folks at NOIR ( ) and they’ve been willing to send me different lens / frame combos to try. The person for my area listens well and I got a surprise in my next box – a second pair with frames she picked out for me based on what didn’t work about the ones I’d tried. It’s the best so far. My head is between adult and kid sized so it’s difficult to get something that fits. If you absolutely need something that works and will be wearing them a lot (I have to wear mine in the morning too; it’s complicated), I think NOIR is totally worth the price and if you’re an individual consumer, they’ll work a little with you. The posted prices for some of their stuff is for wholesalers.

        I have 2 pairs of sunglasses nearly identical to the lens color I ended up with. One blocks the light that keeps me awake, the other doesn’t. I can tell by how I feel compared to the NOIR glasses.

        The lens colors are typically created by pigments and dyes in sunglasses and whatnot. There are a million different ways to make the same color since our eyes only detect a few colors and our brain makes the rest from those. Regular glasses or goggles may or may not work. If a lot of other people say it works, it may work for you. The wavelength we are most sensitive to is the average. You may fall at one end of the spectrum and find what works for most people doesn’t work for you. There are several companies that test their lenses against the full spectrum to ensure there are no “holes” above the cutoff threshold. I found NOIR and their customer service has kept me working with them and I haven’t tried any of the others. They’re expensive but right now (I plan on ending up with 2 pairs) I must have 6 pairs of glasses from them looking for that second pair…. Just my opinion of the company.

      • I have put together a list of 10 different blue light filtering options (for computer work). Each alternative comes with a corresponding spectrogram or some reference as to how much blue light they might filter.

        I hope some of you find it useful!

        • After reading from your site that computer blue light cause retina damage I conclude that you are incompetent and dont read further. All symptom you describe its not caused by blue light but rather near work you get far more blue light from sunshine day than from electronic device.

      • Thanks for the info about the lighting gels, Hank! You just saved me a lot of money and aggravation. I’ve been wanting to put something over my TV for the longest time, but kept putting it off till they came out with blue blocking screens big enough. They cost quite a bit for the biggest size right now and it wouldn’t be enough to cover my screen at any rate. Unfortunately, the store closest to me only had the orange, but since I already darken my screen a great deal at night and always wear blue blockers after sunset, it should help a lot–thanks again 🙂

  22. I’ve used f.lux and it is wonderful, especially for my phone when I want to read Chris’ articles late at night :). I have a nagging feeling this is at the root of my lagging energy and endless hunger since I do unconsciously look at screens late at night and seem to wake easily in the night. I may try the amber glasses but I also have a lens put into my light prescription glasses that filters out blue light. This is a brilliant article and at the root of so many health issues for our modern age, I bet. Now we just need to make all screens without this blue wavelength and we’ll be good!

  23. Hey, I also have this question about the link between artificial light and sleep. I have installed F.lux on my computer and Eye Care (Android app) on my smartphone already. And I have also got a pair of blue light blocking goggles from T’aime optics ( I was able to try out the glasses for a couple nights so far, including in the dark. They really lessened the pain/strain in my eyes, as the lenses turned the screen from a harsh light to a warm easy light. And still in test whether they can improve my sleep.
    Another important thing, try to leave your digital devices now.

  24. I’ve been reading comments here. The problem as set out in various articles is that blue-light emitting light sources — computer screens, TV, and even house lighting — destroy a person’s melatonin, which negatively affects a persons ability to sleep. Almost everyone responding here has bought glasses, computer screens, overnight goggles. etc. The general comment is “they work just fine.” I don’t understand what that means. It’s too vague. What I would like to know is, how has it affected your sleep? Do you sleep longer (how many hours), is the sleep more restful (less tossing and turning, fewer nightmares/dreams, etc)? After reading the comments, I have no idea whether all these gadgets bring about better longer sleep. Please, fill us in. Give us some measurables. Thank you.

    • Hi Jean,

      I wear blue blocking glasses and put them on around 8 – 8:30 at night. I may watch some TV – but I still try to stay away from using my computer or checking my iphone. I am falling asleep faster and staying asleep longer – sleeping 7 to 8 hours. However, I have also made many lifestyle changes – exercising more, changed jobs, now work from home with no 2 hour commutes, getting outside, and I take vitamins and supplements that help with keeping me calm – magnesium, vitamin B’s, liquid minerals, 5-htp, and L-tyrosine. I believe it’s the combination of all these things that has restored my sleep.

    • Hey Jean, I have not used the other products, I only use the blue light screen protectors from for my Kindle and Smartphone.

      Although I am not a scientist, so I cannot give you exact data information, this is my personal experience:

      1) I don’t wake up 4-5 times at night. I actually sleep almost through the entire night. At most, I wake once. Where, before using these blue light blockers, I would literally roll on my bed for hours on end before falling asleep.

      2) My eyes do not strain as much. The biggest problem I had is that I am a writer, so after staring at the computer for a while, my eyes would literally hurt. I had to constantly use the dry eye drops, otherwise I just could not write anymore. Even though I still use the dry eye drops, I only use them in the morning before work.

      3) I am able to sustain a normal work schedule. Before I got my sleeping patterns under control, I no longer have the need to take a nap during the day to keep going. This was a huge problem before because I got so little sleep at night.

      I hope this helps. No scientific data, but true personal experience.


    • Hi Jean, Melatonin is essential. It is likely that a sleep lab would measure a healthier natural production of melatonin levels for the individual who sleeps in a very dark room and limits/eliminates exposure to blue light at night about an hour before sleeping. This has long term health consequences. Short term reports I’ve received from my friends and family include:
      • teenagers- who said they can focus better in school and get better grades in their testing.
      • 50s age bracket- waking feeling rested, clear-headed, happy and energetic.
      That being said, there are a few related essential components to remember.
      • 7-8 hours sleep goal for the adult;
      • Regular sleep schedule. (Keep in mind that your body can produce melatonin even if you’re awake– so long as you are quiet in a dark environment or wearing a sleeping mask.)
      • Bright morning sunshine– rich in the blue wavelengths– is as essential to a healthy circadian as is sleeping in dark-dark environment.
      • Remember to use dim amber or dim red night lights where needed like the bathroom & hallway, placing them as low to the ground as possible instead of at eye level.

    • What happened for me was this:

      I go to bed at midnight. Without the glasses, it takes me about an hour to fall asleep, sometimes more. When I wake up in the middle of the night to go to the bathroom, I can toss and turn for another hour or so before falling asleep again. If I wake up closer to 7am, I pretty much can’t fall asleep again, and then I’m groggy and achy for the rest of the day. If I can, by some miracle, fall asleep, I sleep until 11am – meaning, 11 hours spent in bed, and maybe about 7-8 hours spent asleep. I need 9 hours to feel good, so I was pretty much always groggy and miserable. On days that I could not sleep in until 11am, I was really miserable, but even if I could sleep in like that, it still didn’t make a difference in my mood and energy levels.

      When I started wearing the glasses and the sleep mask, I started falling asleep much faster. It would take me a few minutes instead of an hour. When I wake up at night to go to the bathroom (and I’m very careful about wearing my red glasses to do so), I fall asleep again in minutes. These days, I go to bed at midnight and wake up at 9, refreshed and well-rested.

      So yeah, this blue-light trick was a life-saver for me. I appear to be unusually light-sensitive – the friends and family to whom I’ve evangelized about it haven’t had such a dramatic change – but there it is.

  25. So my dad recently installed Bright White light bulbs around the house to replace the more yellow toned “Soft White” lights. The Bright Whites are a much brighter white/blue tinted light. They are the same 14 Watts. Do the differences of these light bulbs make a big difference?There are actually many restless people in my home. .

    • > my dad … bright white
      Incandescent, or fluorescent, or LED?

      Yes, older people need brighter light, and the lens of the eye gets yellow with age so they get less blue light to the retina. That explains all the elderly women with “blue hair” — to them it looks bright white; shampoos use optical brighteners to make that effect.

      If people in the home want to test whether this interferes with sleep, test by switching all the “white” off about 8pm.

      For the test use whatever’s handy after 8pm until bedtime.

      — cheap yellow lights (compact fluorescent “bug light” will do, though they’re _very_ yellow; or

      — GE “Post Light Bug Light” CFLs which have a less obnoxious but still effective yellow filter — or

      — amber LEDs which you can find as “turtle safe light” — or

      — auto supply store cheap 12-volt amber LED lights — or

      — plain incandescent bulbs with the amber color coating (the 15 or 25 watt ones work great inside older refrigerators to replace the white bulbs the same size so you don’t ruin the sleep-safe lighting by opening the fridge at night).

      See if it makes a difference.
      Your mileage may vary, as they say.

      You can spend a whole lot of money, or not.

      More at:

    • Yes John. The spectrum of light makes all the difference in the world. Blue-rich light is appropriate to help keep people alert. Use it in the home, school and office during the daytime –if a sunny window is not an option. Use it in the breakroom and office for the late shift worker who needs to keep alert at night. (In the case of hospital workers, care should be taken that the blue-rich light does NOT stream into the patients’ rooms, and also the monitors in the patient’s rooms ought to be covered with a blue-blocking film.) Blue-rich bright white is not appropriate for use at night — especially within a couple hours before bedtime– in a typical home setting with children and adults seeking normal sleeping hours. If your dad seems to have a craving for blue light, the first essential step is to ensure he’s getting a healthy amount of blue sunshine type light in the morning. Blue light during the day, especially the morning, is essential for healthy circadian rhythmicity.

  26. Just so you know, I am a licensed optician with over 28 years experience. Over the past 5 years my wife and I have been developing solutions related to blue light problems and reading solutions. We have come up with several great ways to solve these issues as long as you don’t mind wearing glasses.

    We custom craft our eyewear for folks that either:
    Don’t require correction.
    Need reading powers.
    Need prescription lenses.

    Our products start at $59 with these solutions.

    1. Our Mojo BluBlock AR Coating is an anti-reflective coating that filters the bad part of the blue light spectrum, Near UV-A and UV-A and B (UV400). It also reduces reflected glare.

    2. Our Mojo BluBlock Tints are available as options on many of our products. These are available in 3 colors, Amber, Brown, and Grey. All 3 tints filter all of the Near UV-A, and UV-A and B (UV400), and each color provides different features.

    Mojo BluBlock Amber- 15% depth for indoor, nighttime use is recommended. 30% works well for nighttime and daytime computer use. 45 to 60% tint depths are for outdoor use.

    Mojo BluBlock Brown- 15% depth for indoor, nighttime use is good but does not offer the same level of contrast that the amber color does. 30% works great for daytime computer use. 45 to 60% tint depths are for outdoor use.

    Mojo BluBlock Grey- 15% or 30% for indoor daytime use if you are light sensitive. 45 to 60% tint depths are for outdoor use.

    The feedback we have received from our customers has been exceedingly positive. Please check us out. We are a mom and pop shop and do not advertise much. Your feed back would be appreciated.


    • I suggest you also add red tints that block both blue and green. Some folks (myself included) are sensitive to “green” frequencies as well as “blue” ones. I wear red laser-safety goggles from NoIR that block any frequency below 550.

  27. Just a quick reminder… Whether you fall asleep or not, darkness is key to essential melatonin production– at least from the vantage point of your eyes. That is why a sleeping mask can be useful. If you can’t fall asleep, but are still quiet and comfortable in the dark, “rest assured” (pun intended 😉 that your body is still producing melatonin. The flip side of this clarification is that even though you might have slept a solid 8 hours, your body did NOT produce a healthy amount of melatonin if you slept with: a streetlight shining through your bedroom curtain, a hallway light shining into your room (unless it was a dim amber or dim red), a TV or computer screen on, etc. (unless you managed to keep your sleeping mask on throughout the night). Most of you on this forum know that lack of naturally produced melatonin may increase the risk of breast, colon, prostate, pancreatic cancers; some lymphomas; type 2 diabetes; obesity; heart disease; mental, mood, memory and sleeping disorders; interferes with the effectiveness of Tamoxifen, a breast cancer chemotherapy drug; and so much more. If you have a special interest in a particular disease, do an internet search for melatonin/ circadian disruption/ and plug in the name of the disease you are researching. Happy dreams everyone.

  28. I use red instead of orange goggles – they work much better. Mine are expensive laser-safety glasses from (the KRY filter) – pricey but worth every penny. I have tried a few other types and they still let some blue/green light through and my sleep was worse.

  29. I’m awaiting delivery of a pair of Uvex goggles; meanwhile, I’m wondering about my getting ready for bed routine: the first thing I do is take off my makeup. Obviously, I can’t do this in near darkness or without taking off the goggles. So if I wear the gogs for, say, 2 hours before preparing for bed, will any benefit from them be negated by taking them off while getting ready for bed in a brightly-lit bathroom? (I’m generally in the bathroom for about 10 mins.) Please don’t tell me I have to remove my makeup by candlelight …

    • Hi Laura, We use amber night lights in the bathroom, hallway and bedrooms at night. This is best practice to minimize circadian disruption. I purchased them from lowbluelights-dot-com. I do not recommend using bright lights in the bathroom at night.

    • When I wash my face at night, before I take off my amber glasses I turn off the bathroom light; I can see well enough to do what I need to by the light of the hallway or another nearby room. Works for me!

  30. UPDATE: Ok, so I received the blue light screen protector for my Kindle from the folks at I have been using it for just about a week now and I have to say I really like it. I think the biggest difference I noticed is that I can read for longer periods of time, without my eyes getting tired or fuzzy. So my conclusion is that somehow these blue light filters really work.

  31. I have recently introduced many blue block options for folks that need reading glasses (or no power) on my site,
    I offer custom crafted readers with options like blue block tints and blue block anti-reflective coating.
    I know this is “ad-like” but we are the first and only site offering these solutions.

  32. This is so true ““blue light is the most melatonin-suppressive”! I use the computer a lot, and I had no idea my sleeping problems were caused by the blue light emanated from my computer. I recently bought a blue light screen protector from and so far it seems to be helping a lot. As a matter of fact I just bought another one for my kindle!

  33. Wow – just spent 2 hrs reading all the comments. Thanks to all of you. I was about to purchase an e-reader for my grandchild and had heard about some problems with the light-rays. I’m thinking the simplest thing I can do is purchase an amber sheet somewhere and put it over the screen? The child is only 9 yrs old and probably “glasses” won’t survive long. I was considering the Kindle Paperwhite. Books only, no Wi-Fi. The child loves to read books but travels a lot so an e-reader would be helpful. Or, where can I purchase a clip-on light that blocks out the blue? Name of product? I never knew there was this problem, so am grateful for the information.

    • No, do not get an amber sheet unless it’s not a touch screen. The sheets do not work with touch screens. Low Blue Lights sells an amber filter for ereaders, tablets, and phones, but it doesn’t work if you don’t have a glossy screen (a lot of the e-ink screens are matte. I wound up buying a beam ‘n’ read light, which works fairly well, though I think even the 3-bulb version is brighter than it needs to be.

    • Joyce, two models of the Beam n Read Hands Free Lights include filters (orange and red) that block blue light. Spectrum charts of the light with and without the filters can be found on The lights are worn around the neck instead of clipping on a book so they work nicely with all reading matter including hardcovers, paperbacks, ereaders, and even newspapers. Also for tasks like quilting, knitting and crafts. The lights can be found on, Amazon, and many quilt shops. The 3 LED model is currently the #2 Top Rated book light on Amazon. Two product reviews you might find applicable: a Dec 8 review on the blog “Not Everyone’s Mama” includes comments from her 8 year old daughter (; and a Nov 10 review on Reading for Sanity ( commented on her child’s use. My wife and I both read in bed using the filters. Disclosure: My dad invented the light and I work for his company. Email me if you have questions ([email protected]). There’s an 18 LED clip-on with amber LEDs on but I don’t know much about the light. I haven’t come across any other reading lights directly addressing this issue. However, there are some headlamps and clip-ons that have a red LED (typically just one) which could be another alternative.

        • Rudee… I’m a 55 year old woman that has suffered from insomnia and dry eye problem for years. I spent hundreds of dollars on new mattresses, window blinds, and other things that did now work. I had no idea the problem was my computer use. I am a writer, so as you can imagine this is a huge issue for me.

          I am in awe, that when I finally find something that actually works, people like you are more interested in trolling, than actually appreciating the fact that we want to share a solution, which without a doubt, hundreds out there suffer and don’t have a clue as of the why. You may want to think through next time before posting.

    • Hello Joyce, sells blue-blocking filters for many electronic devices. In my opinion, I believe all light emitting e-devices oughts to come standard with a removable blue-blocking film with the warning that using this device at night without the blue-blocking film can be harmful to your health.

    • Hi Joyce,

      I got my blue blocking films online from I also purchased several amber night lights & blue-blocking goggles ( I gift them out) from the same place. I believe that the light emitting e-devices that are expected to be use at night, should come STANDARD with removable blue-blocking films… with a warning that using this device at night without the blue-blocking film could be hazardous to your health — and the health of others sharing the room with you.

  34. This is a really well-researched article! As someone in the lighting research field, my only observation is that light levels in people’s homes are typically much lower than the levels in the chart you linked to. 300 lux is typical for an office, but if you actually measure light levels in your own home under artificial lighting they’re typically in the 5-50 range. So the self-luminous screens (phones, TVs, tablets) are by far the biggest contributors to melatonin suppression in most households.

  35. Chris- thank you for this great article! My husband has a difficult time sleeping, and I’m always suggesting that he shut down his electronics before bed. He is also on the computer all day for work, and he gets terrible eye strain. Doctors have never been able to diagnose the problem. We ordered the goggles you suggested, and they completely eliminated his eye strain! He told me that these goggles have changed his life. Thanks!

  36. I have been reading this article with great interest .This year I was diagnosed with Irlen syndrome .it is sometimes refered to as scotopic sensitivity or visual stress .I am now wearing Irlen spectral filters which are glasses tinted with colours that filter out the spectrums of light that are harmfull to me . These glasses have had such a phenominal effect on my life that I find it hard to make anyone understand as Irlen syndrome is seemingly relatively unheard of in the uk .one of the most profound ways they have affected me is that this winter I haven’t been seasonally affected ..usually I feel so tired and almost drugged at this time of year .I am also very over weight and have always had an appetite that would never go away .The glasses have stopped my appetite or that craving feeling inside .I do still have trouble sleeping but its going to take a while for me to readjust .now if I take off my glasses I tense up and I can feel the stress that artificial lighting causes and I would urge anyone to look up Irlen syndrome .It is possible to buy overlays that can be placed over computers and other screens but these don’t help the stress from lighting which is all around including sunlight .

  37. Well… That’s definetly changed my night time schedule. I no longer use laptops but I’m thinking on getting those glasses

    • thats great. I need a amber googles of cheap and best quality. Can u tell me where u purchase ur googles. And my another question is , wearing googles at night will break it i think due to our unconsiousness movement?

      • Chris says in the article how you can buy them form Amazon. I don’t shop via Amazon. I don’t like how they treat their workers. You don’t need to wear them when you sleep (just make sure your room has as much artificial light blocked as possible).

      • Mohamed,

        Your room should be pitch black dark ( you should not be able to see your hand in front of your face). Research shows that even 1 lumen of light is enough to disrupt the circadian– unless it is dim red or dim amber night light. Use room darkening curtains — or just hang heavy towels over your regular curtains at night. If this is not possible, then wear a sleeping mask. My husband & I both wear sleeping masks that have eye cavities– so it does not touch the eyelashes. I cannot wear any other type. I buy the sleeping mask at Dream I buy the eye goggles at, and believe it is the best available on the market. I have followed their research & story and long time, and called them up too.

    • This is definitely a real concern. Tried the cheaper uvex glasses first and now use a brand called melatonin shades— much much more comfortable on the face.

  38. Has anyone tried using the increasing array of smart led bulb options coming available to control night/day lighting? (e.g. Phillips hue). Sure, they are be a bit pricey, but I like the idea of having something that can be set up to automatically adjust between a standard white spectrum during daytime and red/amber at night. If feel like this is more convenient than having several different bulb types. Before I make the investment, I wanted to see if anyone else had experimented using with these for better evening lighting and if there are any opinions or recommendations on the best products to use. Thanks.

  39. Light late at night can significantly reduce your melatonin synthesis. Let’s not forget the IARC (International Agency for Research on Cancer) has classified light at night as a class 2A carcinogen – placing it on the same level of severity as the effects of tobacco smoke on lung cancer. Good to see you covering this important issue Chris.

  40. The goggles are fine but the ereader is still emitting too much light even on the dimmest setting. This is bothering my husband. Isn’t there an amber shield we can buy for ereaders? I can’t seem to find one! Thanks.

    • > amber filter

      — try medium amber, or yellow Rosco theatrical filter gel.
      Any theatrical supplier and most good photography stores sell these for $6-8 for a 22×24″ sheet; cut with scissors. Tape on one side and you can flip it on and off easily.

      There are other brands also available, ‘oogle will find them.

    • I suggest a sleeping mask for your hubby. My hubby won’t sleep without one. Check out online dream I recommend the sleeping masks that don’t touch your eyelashes… they have a contour shape on the inside. Much better than the other ones. PS I have some reservations recommending dream essentials because they sell BLUE LIGHT EMITTING GOGGLES to help you sleep. This is insane and goes against science. Robs desperate people of their money. However, I still think their sleeping masks are nice & decent price.

      • Thanks. He doesn’t like masks–tried it. I use one myself, prefer organic cotton, but actually lately I’ve been using a silk scarf, which is probably a little sexier… 😀 The Beam ‘n’ read light seems the best solution I’ve found, though I would still love to have a filter for the ereader…

        • Did you try the sleeping masks with the contoured cut-outs — so that the mask doesn’t touch the eyelashes? For me & my hubby, it makes a big difference.

    • Hey, it doesn’t just affect your sleep. It also affects your eyes. My eyes always burn after using the computer at night (or watching Netflix on my phone before bed lol). The apps are great, but they don’t help against computer vision syndrome. There are amber glasses, but I haven’t seen any amber screen protectors. There are blue light blocking protectors that help fight against, not only the artificial light, but also against eye fatigue/ eye strain.

      I have read many articles on blue light and found out it affects more then just our sleep.

      Today, it is common sense, cigarettes are bad for us. 50 years ago that wasn’t the case. This goes hand in hand with artificial light today.

  41. Great article and thanks! Here I’d like to share my solutions to blocks out blue light effectively:

    * For computers, there is software that adjusts the screen colors automatically to the time of day or room you are in. This one is free for Windows:
    * For Android phones, you can use blue light filter for eye care:
    * There is preventative eyewear that can be purchased in a yellow tint or clear tint usually from websites such as or
    * And finally, I found this article that gives some recommendations on how to protect your vision:

    • Here’s why I pop in to debunk the claims:

      People believe the advertising.
      Even _scientists_ believe the advertising.

      Here’s a published study from a reputable journal that was done _assuming_ the “f.lux” claim to remove blue light:
      Does one hour of bright or short-wavelength filtered tablet screenlight have a meaningful effect on adolescents’ pre-bedtime alertness, sleep, and daytime functioning?
      M Heath, C Sutherland, K Bartel… – Chronobiology …, 2014

      … More independent studies are needed to assess the effects resulting from f.lux, especially with varying doses of light (eg 1 hr vs 2 hrs before bedtime). Due to funding limitations, we were unable to concurrently measure melatonin during light exposure…

      They _thought_ they were measuring screens adjusted to be without blue and did not find that made much difference.

      I emailed them the spectra and asked how they did the study.

      They didn’t know about the spectra — and hadn’t checked what was coming out of their screens when using f.lux.

      “The easiest person to fool is yourself.”

  42. > warm white lights instead of cool whites.

    Previously debunked; you can look the spectrum up and see the blue peak is present in both types. Warm white adds more to the red end, but doesn’t lose the blue.

    Look up turtle safe lights.

    • > f.lux
      Previously debunked. Your screen backlight, whether LED or fluorescent, is a blue light source. Warming up the color temperature does not remove that. That’s hyped a lot but almost nobody actually checks the spectrum emitted (which will be unique to your particular model of hardware, of course).
      You can look this stuff up.

      One trustworthy source:

      • So if my screen is black, it’s emitting a backlight? How about red? A purely red screen is emitting a backlight with blue in it? And if I add green to make it yellow, it’s emitting blue?

        With a desktop LCD monitor, white is all three colors activated. The LED pixels themselves are bright in their own spectrum. I don’t think there’s a generic backlight for that. Yellowing white colors is simply reducing the amount of blue in it.

        • You can check your own screen yourself:

          You are confused about how a LED monitor emits light. The pixels aren’t glowing — you can look this up. LMGTFY:
          Monitor Buying Guide – CNET –
 › Computer Accessories › Monitors
          Nov 22, 2013 – This is the type of LED backlight most commonly used in today’s monitors and features white LEDs aligned along the edge of the monitor matrix …

          You can look up the emission spectrum of white LEDs. LMGTFY:
          See the spike in the blue? That’s the 400-500nm range that regulates melatonin

          Black monitor? Try turning off the room lights. Can you find your monitor? Yes, that minimizes all the light coming out. Do you find it useful that way?

          And — just guessing — let’s assume you are a rather young person. If so your sleep pattern is consolidated and very hard to disrupt. None of this will matter for you. If you were a newborn or an older adult, your experience would be different.

          Get your facts correct — read up on how LED monitors work, and measure the spectrum of the light sources around you if you care to spend the $40 or so for the spectrometer kit — and your opinions will carry more weight because you can combine your personal experience — that light doesn’t affect your sleep — with the facts about the physics and biology that are relevant.

          Seriously — this is a chance to do science and educate others about how to learn the world. What we find incredible is a good place to start.

  43. “warm white” LED or CFL has a big spike of blue in the emission spectrum.
    It’s just adding an additional phosphor that increases the red-yellow end to warm up the appearance. But you still get a lot of blue from those.

    You can look this stuff up:

    and see earlier links. You can find low/no-blue sources (and inexpensively too, you can pay a tenth as much as you would for the ones that promote themselves — but you’ve got to know the spectral curve to identify them).

    • Modern “Cool-White” LEDs usually have even higher 450nm emission than “Warm-White.” Last year the LRC did the hormone blood test showing that cool-white suppressed twice the melatonin as warm-white. But Warm-White has too much 450nm anyway.

      Cool and warm labels are not adequate representation for health purposes. These tie to CCT (correlated color temperature), a single number which comes from a multitude of values. Helping to understand, CCT can be thought of as a dollar amount shown on a bag of coins; that can never
      tell how many quarters, nickels, dimes or pennies are within. A bit technical, see the last paragraph on this page

      Modern white LEDs are based on a chip intentionally radiating approx. 450nm wavelength which is centered in the ipRGC spectrum, coincidentally, right where it hurts. Cool, warm, and neutral whites are made with different phosphors over that nasty chip, but some 450 is allowed through to color mix. If the display backlight in your device, or the room lighting have the modern white LEDs, color filtering is essential for your health.

      The large LED makers are now adding name to OLED production because that is not dependent on the nasty 450nm chip. However OLEDs can produce any of the colors they desire and our safety prediction still requires knowledge of its Spectral Power Distribution (SPD).

      Next we must provide a Health Safety Rating method for a number on all lighting since finally, having OLEDs available, health insurance rating is on that forefront.

  44. Here is my advice. Use a plasma T.V. Hook your computer up to it. Plasma T.V.’s are powered by gas to display the image. Use Incandescent bulbs. Prevencia glasses are really good as well. They block blue light but cost a lot of money. Totally worth it in my opinion. Stop using your cell phone so much and go outside!!!:)

  45. > ambien
    Check this:

    > melatonin
    Your body starts to make its evening dose a couple of hours after your last exposure to blue light.

    Remember, if we dose the body with a chemical that the body makes naturally, the body generally “downregulates” — makes less — naturally. You may want to give yourself a chance to see how you do without supplements for a few weeks and see if normal sleep recovers just eliminating evening blue light.

    • Thanks for the info about melatonin production, good to know. I haven’t been taking it every night, and am confused over proper dosage – I’ve read various articles on it and have found conflicting opinions on an appropriate amount. My take away has been: the less the better.

      Also interesting to read the LA Times article. Just last week I read a comparable, and longer, write up in the NY Times about that same study. Sobering information. But this is the first reference I’ve seen referring to Ambien and its ilk as ” ‘atypical benzodiazepines’ and were not included in the analysis.” I’ve never taken any of those “Benzo” drugs but had been considering pressing my doctor for Xanax at our next meeting (LOTS going on in my life that contributes to sleep problems) – that study has changed my mind.

    • I beg anyone considering it…stay away from Ambien. It’s hell to get off once you’re on it. I finally got my dosage down by half by adding essential oils to the mix but it was really rocky getting there.

  46. I’ve been reading about concerns over blue light pollution so was glad to have found this article, and also the link to the Uvex glasses from Amazon. Before I bought anything, I did some comparison shopping at both and sleepzzz – crazy price differences. I decided to get the Uvex item you linked to and also an additional Uvex that looked bigger, hoping it would fit over my prescription glasses – and they do! The item is Uvex S0360X Ultra-spec 2000, and was offered as a “You might also be interested in” at the bottom of the page for the first Uvex. At less than $9 each, I bought them both. The second pair is a perfect fit over the prescription specs I wear at the computer. I’m also trying the f.lux app, but when I have the Uvex glasses on, I turn off the f.lux.

    The 2 big issues I’m dealing with in trying to improve my sleep patterns are an over dependence on Ambien, and TV and computer use too close to sleep time. (There is a 3rd issue but it’s largely out of my control: I’m 63 with a big old prostate that gets me up a couple of times a night. I can deal with being awakened, but usually have trouble going back to sleep. I used to take a half tab of 5 mg Ambien before getting in bed, and then the other half the first time I get up. But the more I read about Ambien, the more leery I am of over using it.)

    I’ve only had the Uvex glasses for about a week but have high hopes. I can feel my eyes getting tired as I watch TV late into the evening – I never get in bed till at least midnight or later, with my last hour usually in front of a computer. So now I’m putting the glasses on about 9:30 or 10. I sit at least 10 feet or so from the TV, but no more 18-20 inches from the computer screen and I think the monitor light blast that late at night was causing noticeable eye fatigue. It could be wishful thinking, but I think I feel less eye fatigue when wearing the glasses.

    I suppose (I know) I could give up that last hour at the computer, but I’ve always used the TV to lull me to sleep – I love the sleep timer function built into modern TVs. But I don’t want to fall asleep with those big glasses on, so I splurged at and just ordered an amber filter to fit over the screen. The one I bought is the smallest at $80, so I’m really hoping it works – at least I can fall asleep without the glasses on.

    I’m also supplementing the blue light control with a little OTC melatonin before bed. I buy 3 mg tablets and cut them in half – taking one half at bed time and another half when I first get up during the night. Results are still out but I’m hoping for the best.

    • Patrick, I’m your age and can relate to several items you mention although I don’t take meds and usually spend the evening until late in front of 2 flat panel displays with some TV time in between. I also have some parenting responsibilities that keep me up much later than I want. I got started with cutting back on blue light after adding blue light blocking filters to a reading light I market and use for reading in bed at night. I recently started wearing the UVEX glasses for some time before going to bed. Several suggestions for you. First, stop using your computer and watching TV earlier and switch to reading either with printed books or an ereader that uses e-ink. TVs, computers, tablets, and cell phones have pixels that flash on and off. E-Ink devices (and books) are static and easier on the eyes. When I turn the computer off earlier and switch to reading, I get sleepy earlier. I never realized the impact those flashing pixels have until I started reading with my Kindle every night. Second, do use the orange goggles for a couple of hours before going to bed. When I get the goggles on later, I can tell I’m more wired when getting into bed. I adjusted f.lux to a lower setting than the default but late at night use the goggles on top of f.lux as I think some blue light still gets through. But even with both the flashing pixels will impact you. For reading in bed, use the orange goggles or you can get a Beam n Read light that has the blue light blocking filters. I like reading without the goggles but then of course I’m also biased about my dads’ invention. One nice thing about e-readers is you can bump the text size up to make it comfortable to read even with aging eyes. So if you haven’t been into reading in bed, try one of these gizmos out.

    • Check out essential oils to help with sleep. I use a combination of Cedarwood, Lavender, Peace & Calming, Aroma Life, and Sleep Essence capsules (lavender, vetiver, valerian, and Ruta graveolens essential oils with the hormone melatonin).

      I’ve been able to cut my Ambien dosage back by half with that combination. Looking forward to getting off it for good.

  47. I wear the amber glasses before bed (not after sunset) Here is a question, when watching tv, is there a ‘least bad’ option? We have a real home theater set up in the basement. We use a projector on a screen. Does that put less blue light back into our eyes than an LCD screen?
    When watching movies, I don’t want to distort the image with amber.
    I made the rule that movies are done by 10. I’m wondering how else to limit it, where we still enjoy ourselves. We put the baby to bed around 730, so there isn’t a lot of room too be it up further.

    • That web site for OLED is very informational. There I found important specs for that table showing Melatonin Suppression, meaning it refers to 100 Lux for 1.5 hours exposure.

      In looking for that data I found a very important statement as follows:
      [Accordingly, medical experts have called for the development of new lighting sources with low color temperatures—free of blue emission—to safeguard human health.]

      • “…medical experts have called for the development of new lighting sources with low color temperatures—free of blue emission—to safeguard human health.”

        Well, off the top of my head — FIRE would fit that description. Could the next great technology in healthful illumination be the OLDEST?

        Could be a real boon to folks in the candle business…

    • I have no idea whether the phone may be causing eye damage but I just wanted to say that being the “only reasonable cause” seems a bit strong.

      Surely it could have been about to happen otherwise (for historic reasons) and is just coincident with the new phone. Correlation does not equal causation after all.

      But I hope whatever is affecting your eyesight, it doesn’t get worse.

    • > the only reasonable culprit
      Are you quoting your opthalmologist, or are you using logic?

      This sounds to me like you’ve noticed nearsightedness rather suddenly — not a retinal tumor, or cataract, or something like that. Am I right?

      If so I’ll tell you what my eye doctor told me when I was suddenly unable to focus well: the lens slowly gets stiffer as we age so the speed at which we can change focus changes (“accommodation”) — and correspondingly the little muscles all around the lens that have to work to change its shape have to work harder, and harder, and harder over months. And, one day, they give up; they just can’t make that lens material bend sufficiently, so they relax.

      Bingo — suddenly you’re nearsighted.

      Just guessing, mind you. But if you haven’t gotten a diagnosis from a real eye doctor — not an optometrist but an opthalmologist — you can be missing all sorts of changes, some normal like this one with age, some dangerous and without any symptoms like pressure increase in the eye.

      None of that has anything to do with the pineal gland.

      Oh, and whoever wrote the headline on that blog takeoff from the IBT story isn’t someone you should trust to tell you the sky is blue — that’s just scare words.

  48. You better shop around.

    I’ve long thought the prices at lowbluelights were high, e.g.

    but that site charges more.

    Definitely shop around. Remember, all automobiles use 12v amber LEDs and they’re cheap.
    Trying to position these as “health aids” or “medical appliances” at huge markups kind of sucks.

    Good review on the subject at:
    “Developing Architectural Lighting Designs to Improve Sleep in Older Adults”

    (that one has been plagiarized leaving the authors’ names off it by some bloggers out there — always ‘oogle some text and see where else it appears if you’re not sure who wrote something)

  49. I came across this interesting youtube on a new house design: Adaptive Circadian Lighting — Honda Smart Home US
    “The LED lighting used throughout Honda Smart Home is… designed to support the health and wellness of the home’s occupants. Honda worked with researchers from the California Lighting Technology Center at UC Davis to explore new circadian color control logic. Mimicking…”

  50. This is a great article, thanks! I’ve only discovered the significance of blue light this week – comparing this to the volume of replies, I’m wondering where I’ve been. 🙂

    Don’t know whether I can suggest a book? But I’ll have a go, considering what the book contains. It was written by Richard HanslerMD who’s one of the’s founders. Its packed with scientific data from research, it’s not a light read – but one I think would be appreciated by this website’s readers.

    The book’s on Amazon and is just over a dollar.

    Another Weightloss Gimmick? Maybe Not : Eliminate Blue Light – Maximize Melatonin – Develop Brown Fat – Burn White Fat.

  51. Well, I’ve been sending this information to my local city council office for a year or more.

    This week the city started replacing the streetlights with the blue-white LED lamps.

    Lesson learned: industry has a huge backlog of the blue-white LEDs and they’re pushing them out the door at fire sale prices, telling cities that the savings in electricity will pay for the whole replacement process. I heard back that the city engineer asked their LED supplier about the health problems I raised and was reassured that the blue-white LEDs are “industry standard” for replacing streetlights.

    It’s true that the old blue-white LEDs cost less electricity to run.

    By asuming there’s no cost to anyone from the health effects, so there’s no later cost of filtering or replacing these LED lights, which will last 30 years — then putting them in can be a no-brainer decision by city government.

    Oh, wait …

    In other news, safer LED streetlights are already coming on the market:

    “Color temperature, intensity and blue spectrum of the light affects the ganglion receptors in human brain stimulating the human nervous system. With this work we review different methods for obtaining tunable light emission spectra ….”

    ” Thermal, optical, and electrical engineering of an innovative tunable white LED light engine “, Proc. SPIE 9003, Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XVIII, 90031B (February 27, 2014); doi:10.1117/12.2040599;
    Light at night and melatonin have opposite effects on breast cancer tumors in mice assessed by growth rates and global DNA methylation

    February 2014, Vol. 31, No. 1 , Pages 144-150 (doi:10.3109/07420528.2013.842925)

    • Hey Hank, I really want to thank you for your comments here and over at psycheducation; they’ve helped fill in a lot of the blanks for me regarding the whole topic of light & health.

      One question I would like to ask: do you have any knowledge on how much UV radiation is emitted by TV and computer screens? I anticipate your answer for TV’s will be “It depends what type of TV.” I have a flat screen LCD TV. My computer is a laptop, which of course is also LCD. (As I’ve been able to gather from Patrick Mullins’ posts, all LCD’s are back-lit by LED’s, which I imagine must play into the equation of this particular issue)

      My thoughts on this, as much as I’ve gathered so far researching light, is that for LCD TV’s – even if there are any UV rays – that it’s probably a non-issue unless you sit 6 inches away from the screen. My particular thinking for this is that if you read the article & reader comments for the following link, you’ll see in the comments section that the author of the article indicates to a reader that the intensity of red & infrared wavelengths diminishes the farther back from the lights you are: (this article & the reader comments is a great read in itself)

      However, I could be completely wrong, as red & infrared are at the other end of the spectrum – I’m welcome to being corrected – perhaps the higher energies of the shorter wavelengths allow them to travel further whilst maintaining their intensity.

      With laptops/computers on the other hand, since we do sit really close to these screens, I’m guessing if indeed LCD’s/LED’s emit UV rays then it’s probably pretty important to filter them out?

      I did read your comment that you lay the roscolux uv filter #3114 over your screens along with the #23 orange filter. I just want to know if this is totally necessary with TV’s, because I live in Australia and I’m in the process at the moment of trying to find a supplier that will cut-to-size the roscolux filter gels; so far I’ve only been told that the only option is to buy a whole roll which is upwards of $150 without even adding on shipping. I’m not particularly concerned about it for my laptop as I’ve got some Uvex S1933X’s coming in the mail. (if anyone is wondering why I don’t just use the Uvex for TV as well as computer, it’s just a personal comfort thing – I’m willing to spend a little bit of dough for the sake of more comfortability when unwinding at night.)

      Anyway man, get back to me. Thanks dude.

      *on a sidenote, if you happen to know of any websites where you can directly order custom sizes of roscolux, please let me know

      • If you wear the blue-blocking glasses, you won’t need any filters on the computer or tv monitors. Low Blue’s lab have the best products… from the glasses to light bulbs to filters. You can trust the quality and effectiveness of blocking only the blue. I called them to personally talk to their engineers and have been following their products for years.

      • Filter gels — look not by the name Rosco but rather ask generally, at photography suppliers and theatrical suppliers. There are several other companies that also make color filter gels, usually in a standard rectangular size that fits standard holders used in both photography and theater.

        UV — don’t know.

  52. Good recent review article:

    Breast cancer and circadian disruption from electric lighting in the modern world

    Richard G. Stevens, George C. Brainard et al.

    Article first published online: 24 DEC 2013
    DOI: 10.3322/caac.21218
    Issue CA: A Cancer Journal for Clinicians
    Volume 64, Issue 3, pages 207–218, May/June 2014

    — excerpt follows —-
    In 1980, the first clear evidence was published in Science that ocular exposure to bright white light during the night could suppress melatonin production in young adults.[31] Since that seminal report, great detail has emerged on the impact of wavelength, intensity, duration, and time of night on the acute suppression of melatonin production by light. Similarly, much more is understood about how light resets the timing of the circadian clock and the rhythms it controls, often measured from the timing of the melatonin rhythm but also including cortisol, core body temperature, and circadian gene expression.

    Initially, it was thought that bright light, at least 2500 lux, was required for melatonin suppression in humans.[31] More recently, however, it has been shown that, under carefully controlled conditions, retinal exposure to illuminances of as low as 1 lux or less of monochromatic light at wavelength 440 to 460 (blue-appearing light) can significantly lower nocturnal melatonin,[32, 33] as can <100 lux of broad-spectrum fluorescent light.[34-37] These same light levels can also elicit significant phase shifts of the circadian clock and directly enhance alertness[37-40]; approximately 100 lux exposure will cause about 50% of the maximum response. Such light exposure, when experienced in the evening at home from bedside lamps, TVs, computer screens, tablets, and other devices, causes suppression of melatonin, delays the timing of circadian rhythms, and elevates alertness, all of which make it harder to fall asleep, make it harder to wake up in the morning, and restrict sleep.[36, 41]

    The physiological mechanism by which light exposure is conveyed to the circadian system is one of the more intriguing topics in modern biology ….
    150 citations, many of them linked, at the main article:

    Enhanced Article (HTML)
    PDF (160K)

  53. > Randall Glass
    > January 6, 2014 at 5:18 am
    > Been doing some more research…..

    Would you cite your sources for the statements you posted?
    From what I’ve read things are a bit less simple than what you’ve written there.

  54. >melatonin
    You can look this stuff up: ‘oogled: melatonin microgram

    (yours may differ, Google gives each user different results, so if you want to get unbiased results flush cache, use a VPN and don’t be signed in or accepting cookies from Google — they show you what you’re most likely to have been looking for, which can be very misleading if you’re searching for medical or scientific information):

    First 2 hits:

    Products: What is the proper dose of melatonin? – Life …
    This article was based on anecdotal reports from some members who stated they had better sleep patterns when taking 500 microgram melatonin rather than … Customer Reviews: Melatonin Timed Release ……/B000X9L8ZE
    I was happy to find a time-release capsule of a low dose (300 micrograms) of melatonin. The megadoses of melatonin that one typically finds at drugstores are …


    National Sleep Foundation:

    “…Because it is not categorized as a drug, synthetic melatonin is made in factories that are not regulated by the FDA. Listed doses may not be controlled or accurate, meaning the amount of melatonin in a pill you take may not be the amount listed on the package. Most commercial products are offered at dosages that cause melatonin levels in the blood to rise to much higher levels than are naturally produced in the body. Taking a typical dose (1 to 3 mg) may elevate your blood melatonin levels to 1 to 20 times normal. Side effects do not have to be listed on the product’s packaging. Yet, fatigue and depression have occasionally been reported with use of melatonin. …”

    Links and full text at the source.


    “It’s a poor kind of memory that only works backwards” as the — The White Queen, in Through the Looking-Glass.

    When we post medical advice to the Internet, relying on what we think and remember guarantees outdated information, and sometimes mistakes. That’s not about you or me, it’s about checking what we remember.

    People rely on opinions from strangers online.

    Do a careful search for current information and provide the links so later readers can check them and do their own updating. There’s always new info.

    I found and corrected 2 errors just checking what I thought, as I posted this response.

  55. I’ve been suspicious of “books on electronics” like Kindle or Nook, specifically because of blue light. Since I know many people read before sleep to wind down, I’m guessing they’re not getting the effect they want if using electronic books! Thanks for confirming my gut reaction!

    • Most eReaders in use today like the Kindle and Nook use eInk that does not project any light so there is no blue light coming from these devices.

      This contrasts with tablets, smartphones, and laptops that use LCD screens that do project light. Just to clarify, the Kindle Fire and Nook HD are tablets not eReaders so those devices would shine blue light.

      The latest model eReaders such as the Kindle Paperwhite and Nook Glowlight do include built-in LEDs but they can be turned off (or almost off). However the companies are still selling models that don’t include lights so you can get an eReader that doesn’t have a lighted screen.

      So with eReaders (and printed books!) you can avoid blue light by using a light fixture with no or low blue light, a reading light with a filter to block blue light, make your own filter and tape it on your book light, or use appropriate colored glasses to block blue light.

      If you want to use an app to read ebooks on a tablet, smartphone, or laptop then you will need to put a filter on your screen or use glasses that block blue light.

  56. Great info. I have Twilight installed on my Android phone today and it kicked on the red filter at sundown. But I’m now wondering about my bedroom TV. Wife and I always watch a little TV before bed and then fall asleep with it still on. Is it possible to adjust the color/tint/brightness levels to achieve a desirable effect as far as reducing blue light? My TV has advanced color settings that let’s me control levels of Color, Tint and Brightness for several colors, including blue. Will this help or is it not the same? Don’t really want to use glasses as I spent some decent coin on my eyes so I don’t have to wear lenses anymore 🙂

    • Hello Chris,
      Your TV comments raise a very important concern on those gadgets. First determine the technology in use.
      Pointer: LED based video devices are less than just flat, they are skinny, meaning a few inches thick at most. The original TV technology is CRT (cathode ray tube) which even for a flat screen, will be maybe as thick as it is wide, e.g. a 20″ flat screen CRT will be 20″ deep. Not very modern in today’s bedroom, except maybe mine.

      The point is that CRT has 3 electron beams, one each for red, green and blue phosphors. The only time 460nm is emitted is when that is a necessary pixel in the particular image shown, including white. Color/Tint adjustment on a CRT will control that precisely as desired.

      The modern flat screen TV is a mere few inches thick. The common basic version has an LCD layer that selectively switches those R-G-B colors from White LED light behind them. The first important issue is that simple method can be changing by manufacturer any day, so be sure you know which, if making a difference. The basic issue in question gets back to white LEDs which cannot reduce their primary emission of 460nm without reducing their basic white illuminance. All colors on that TV screen came from 460nm generation, then filtered by multi-LCD pixels according to the screen color needed. Color/Tint adjust can merely filter that blue that was already produced.

      Is that coincidence? The fundamental emitter of that white LED is precisely the ipRGC trigger (melatonin suppressor).

      Using CRT technology is a major reduction of the blue. Variations of color use may need some blue amount. When no blue or white on screen, then no 460nm generated from that pixel phosphor. Remember that “white” is an equal mix of R-G-B levels, regardless of the source.
      Removing any blue from white – – guess what color you get.

      • So I guess the only solution for LCD owners is to either go back to CRT, or use blue-blocker glasses? Is that what I gathered from your response? Great response, btw. Took me a few days to parse it 🙂

        • Short answer is, yes. But CRT may not solve it.

          The LCD merely controls light from behind it, and, today that is from predominantly white LEDs. Today 99% of white LEDs have 450nm chips to drive their phosphor. Ionized gas methods have been done, but there again 450nm wavelength is generated.

          The CRT emits nothing till called for on its screen, so some pixels can have 450nm. The solid-state screen has white LEDs going full time.

          Mentioned here yesterday was the matter of reading a book from a Kindle (or similar) at night. That white LED screen behind any color text is blasting the retina ipRGC’s a few inches away, with way too much radiation. Melatonin is totally suppressed but eye strain may put you down anyway.
          The recent ZzzQuil stuff is merely equiv. of 2 Benadryl tabs, 10% alcohol and High Fructose Corn Syrup. NO melatonin either.
          You may need at least 3mg of melatonin to offset those white LEDs. Then create your own version of ZzzQ stuff.

          • > 3mg of melatonin

            Whoah! Don’t do that. You’re confusing milligrams (mg) with micrograms (mcg or “mu”g) here.

            You are giving medical advice.

            Mark Twain warned about the health effects of believing typographical errors in health writing.

            Block the blue light and your body will make the melatonin you need.

            Three milligrams is a thousand times more than three micrograms, which is around what you get naturally by blocking the blue light and letting your body work.

            3mg of melatonin is a huge overdose.

            • You are mistaken. Melatonin is effective dosage is in mg not mcg and you do need 1mg of melatonin at least for any effect.

              • Mart, thank you for helping with milligram clarification.

                Another issue in this line is our Pineal gland has lower production as we get older. I’ve observed those at 85 needing at least 5mg, 1 hour before their bedtime. Worked great. One character played solitaire on a 20″ screen 6″ from his face, and changing that background color and card style was of minimal importance, but those 5mg did the trick.

                Nationally known drug and food stores have Melatonin pills in ranges of 1mg through 10mg. We can post here some ages using which dosages that helped on a regular basis. Jet lag, bed-time movies, reading and solitaire are more issues to share.

  57. Ajay mentioned the Hoya “Vision Protect” eyeglasses coating — -that’s not blocking the blue-green band, which controls sleep. That’s around 400-500nanometers.

    The Hoya and other “blue-blockers” are aimed at blocking the high energy blue that does slow cumulative damage over a lifetime — which is down around 400 and shorter, on the way to ultraviolet (the shorter the wavelength the higher the energy of the photons. Once you get into that high energy blue the photons pack enough energy to knock an electron off an atom — that’s where the damage occurs).

    I didn’t know about that; I just looked it up:

  58. Copied out of my posts at psycheducation a while back, as an example: this is a Rosco orange theatrical filter transmission spectrum. See how almost none of the blue light passes through one sheet of this material.

    We have sheets of this or other similar ones cut and taped along the top of our monitors, so we can flip them down and they cover the screen without leaking light around the edges.

  59. PS, for all the questions about glasses and computer and phone screens — again I’m just a bystander reading here, not an expert. But I’d say:

    nobody can answer that for you. Glasses have to fit snugly all around your eyes, not leave a big gap where the blue light comes in. (The blue receptors in the eyeball aren’t at the center, like the receptors used for vision. Instead, they’re located where they detect the color of the sky, more at the top and sides of the field of vision: )

    Asking about what your computer or phone emits depends on your exact light source.

    Re f.lux, I suggest going to LEDMuseum and asking Craig if he’d recheck it — but that’s on _his_ computer not yours so it’s only a clue.

    (If you do use LEDMuseum, a plug from me a bystander — remember, he’s just one guy (disabled, poor, and very smart) who has been doing the world big favors for a long time — I try to donate something to him regularly. Consider doing that.

    What Audrey Fischer April 23, 2014 at 10:56 am said:
    > The only “safe” way is to put a blue-blocking filter
    > on the OUTside.

    Amen. See the psycheducation blog and search for “rosco”

  60. > warm white … CRI
    Be careful about that, because color temperature “warm white” and CRI refer to the average of all the wavelengths emitted — that affects color rendering.

    But there are lots of “warm white” LEDs, almost all of them, that still emit a large amount of blue light — because they’re basically blue emitters coated with phosphors that intercept some of that and re-emit it.

    You _have_ to look at the actual spectrum emitted, and see if there’s a spike in it for emission in the 400-500nm range. Even very “warm white” LEDs still have that.

    You can look this stuff up, here for example (Japanese but the illustrations are very clear):

  61. Hi
    interesting article. I would like to purchase some blue blockers to help with sleep but i need some advice.
    Do all blue blockers work and help your sleep?
    or does it need to be one of the 2 advertised in the article??

    Im considering these ones

    Will they work as well???

    Thanks in advance

  62. Congratulations to Bob Friedman June 30, 2014 for contact with Craig at LEDmuseum to test those filters.

    I began collecting info on light and sleep in 2007– still available thanks to a very tolerant blog host:

    There’s a lot there — theatrical filter types; “turtle safe” amber lights; the American Medical Association’s health warning about light at night; and the caution to watch out for your home town’s streetlights being changed out for high-blue-emitting LEDs, there’s a huge marketing push on by the industry to do that before the health effects stop them.

  63. On another note. According to Ray Peat, production of melatonin is a stress response to darkness, nothing that helps one actually sleep. The less melatonin the better. I certainly did not feel any benefit to my sleep by melatonin supplementation. Melatonin

    “Many health food stores are now selling melatonin, to induce sleep and “prevent cancer.” They have taken some information out of context, and don’t realize how dangerous melatonin is. It makes the brain sluggish, causes the sex organs to shrink, and damages immunity by shrinking the thymus gland. It is the hormone of darkness and winter, and is produced in the pineal gland by any stress which increases adrenalin. Adequate sun light suppresses the formation of melatonin.” -Ray Peat, PhD

    • Kris, The copy and paste you made from that Ray Peat forum is itself out of context. It does not match anything in total from the ray peat web site.
      That forum has its own protective statement, as follows:
      “Disclaimer :
      Content and information placed in the Ray Peat Forum does not necessarily reflect the views of Ray Peat Forum. While it is permissible to discuss medically-oriented topics, nothing posted here should in any way be interpreted as authoritative medical advice. While the information provided by knowledgeable members is certainly available for the education of forum members, Ray Peat Forum makes no claim of accuracy and does not endorse suggestions or recommendations set forth here.”

      There is far more scientific information about melatonin that can help those interested. Our pineal gland produces melatonin naturally for reasons readily available, and in that Peat site there are actually links to scientists’ work with such.

  64. Have you heard of Jim Gallas, inventor of Melanin Lenses for eyeglasses? He recently formulated a blue blocking Melanin lens designed to promote sleep by absorbing blue light, and protecting the body’s normal level of melatonin production. They are tinted amber, which naturally blocks blue light, but also contain melanin which furthers reduces transmission. I know a few people who swear by them.

  65. Good discussion and collection of suggestions, thank you.

    f.lux, unfortunately, doesn’t block the blue emission — that’s the light from either fluorescents or “white” LEDs operating behind the colored pixels but leaks through. Craig at LEDMuseum has spectra for a great many light sources (wonderful site, just one guy’s contribution to the world, worth supporting if you find it useful).

    You can see the big blue light spike there — between 400 and 500nm.

    YMMV of course; babies and older people have less consolidated sleep and more easily get disrupted. Young adults can sleep through anything, mostly. But if you’ve got a baby, try the amber nightlights for night feeding.

    We get around fine using amber LED lights and filtered “bug light” compact fluorescents for a few hours in the evening — they can be bright enough to read by and not interfere with sleep, the way our old CFL reading lights did. Look for “turtle safe” lights — the photoreceptor molecule that handles this daylight detection is ancient and shared by many living things.

    • Hank – Thank you for your reference to the LED Museum with their spectrographic charts showing the big blue light spike of LEDs on the charts. After seeing your post, we submitted our lights with the orange and red clip-on filters to the LED Museum for them to test. Craig has already published his initial analysis (he tested them immediately) and just published his results ( It illustrates that although LED’s do have a lot of blue light, it’s possible to dramatically reduce blue light with simple filters whether snapped on a light, placed on a screen, or by wearing glasses with orange/amber lenses. The “color transform orange” (CTO) filter gels used for lighting in theatres and for and film production would probably work well for a DIY filter.

      • Bob,
        You show a great idea for lighting, especially that used for late night reading near bedtime. A couple hours before sleeping is most critical to eliminate that LED blue spike.

        From the test results you show, I suggest amber filtering for a couple reasons. The most common white LEDs naturally have a deep dip between 475nm and 500nm, so having a filter cutoff through that dip will still protect from the blue, and it will help color rendering, and it will allow more illuminance than orange and especially more than red filtering. Eyeglasses are easily available in amber, but not sure about add-on lamp filters.

        As Hank said, this can be a great suggestion collection place for more healthful and efficient lighting.

  66. This site got my attention when searching for more problems caused by melatonin suppression. I began over a year ago making another web page for lighting, specifically digging into the effects of 450nm radiation. Then the best thing to appear was the lab test publicized by Dr Mark Rea at LRC. And he is involved with the graphic in “blue light and melatonin suppression” here which compares blue LEDs with iPad and orange tinted glasses. That was so neat I added an orange glasses spectral curve option to my site.
    The only problem is that graph here shows only the blue LED, and the killer is the cool-white LED made by most manufacturers. Now, there is one maker that began correcting this poisonous wavelength in 2012 providing warm-white with CRI > 90.

    Over a dozen LED types by about six makers are compared on my page, using the specific formula from Dr Rea’s lab test, showing directly the Circadian Stimulus by any of those, based on illuminance you need. You will see that incandescent bulbs cannot relate to melatonin suppression, but we are getting rid of those. Those used to be the light source to keep on all night while you sleep, with NO harm.

    Cool-white fluorescent and now LEDs are everywhere, specifically because their efficacy is higher than warm-white; so that is where competition begins, it’s money vs. health. Did you know the AMA has written about this cool-white matter for more than two decades? Started with Fluorescent.
    There must be labeling coming to let one know if the lighting they have, or would have, must have limited exposure, how much and when. It was done with UV tanning beds, legal limits on exposure times and how many times per day and week. Why?

    Did you know our lead poisoned atmosphere exceeded 20 years (1950 thru 1974) because of Auto and Petrol companies fighting against the proof that a doctor provided in 1949. We went 20+ years smoking cigarettes before the actual cancer and more, warning label was required by law. Both these warnings, catalytic converters and cigarette warnings came about when the Surgeon General along with a Senator made it happen.
    Today the leading LED makers are keeping this matter behind their door.

    See that comparator page I mentioned at and please let me know of any suggestions.

  67. There is a lens coating called blue protect made by Hoya, available from Vision Express, which reduces blue light to an acceptable level so as not to impair melatonin suppression.

  68. Audrey, or if anybody can respond that would be great. How would you rate those Himalayan Salt lamps? I find them beautiful but I don’t know if having those around the house at night is disrupting my sleep.

    • Hi Andrew, Yes the Himalayan Salt Lamps (HSL) are very beautiful– and very disruptive if they are in your room while sleeping — however, they seem dim enough — and in the amber spectral wavelength — to be appropriate for winding down/ dimming down the light 1-3 hours before sleep. Actually these lights are a very inviting “excuse” to ditch the bright white/high blue spectrum lights at night, and turn on a little ambiance. It would be an interesting question to pose to the manufacturer to ask– what is the lumen level emitted by their HSL? I notice online that some HSL have dimmers available. Research shows that even <1.5 lumens is enough to interrupt the production of essential melatonin.

      • Thank you miss Audrey! Have you seen those studies on the color of rooms and how those influence sleep apparently? It actually seems contradicting because from the study I read, blue and green rooms stimulate the best sleep while red was sort of in the middle tier with royal purple being the worst. What do you think about that?

  69. This is a great article Chris. Mos articles lack the links to scientific research studies, and those don’t cut it for me personally. I’m a ‘show me the data’ person. I’m definitely gonna check out Flux. The only downside seems that colors actually change, which might not be ideal for a graphic designer like me.

  70. Another device that can be helpful to some is the Beam N Read LED 6 Hands Free Light that comes with 2 clip-on filters: a blue-blocking orange filter and a red filter. Worn around the neck, one of the major uses is for reading in bed at night (It’s also used for needlework, caregiving, travel, walking in the dark, power outages and more). Disclosure: I’m affiliated with the company that makes the lights. (Chris – if you’re interested in reviewing the light, contact me and I’ll send you one).

  71. Inspired by this article, I have decided to go on a “technology fast” as a part of an effort to reset my internal circadian clock. I’m going to go camping for a few days and leave my laptop, tablet, and iPhone at home.

    I imagine that the purist would leave her flashlight at home, too, but I want to be able to read. What should I look for in a lantern, headlamp, and/or flashlight? Do LED lanterns produce blue light? I’d prefer to not use something that requires fuel.

    • Cool Vicky : ) I recommend a red or amber flashlight. low blue and many astronomy sites have them for sale. Also, a quick fix is covering the front of a regular flashlight with a piece of red t-shirt material, red balloon, or red plastic tablecloth — fastened with a rubberband. We do this often at stargazing sessions for the public and scouts. Bring a star chart /planisphere so you can read the stars. download a free one with highlights of the month from or astronomy magazine. Don’t forget the binoculars : ) btw, there are lots of astronomy club “star parties” that are open to the public– many free, some even camp overnight with their telescopes. . . willing to share views of the cosmos with all who appreciate the wonders of the starry night sky.

  72. Hi Chris (and anyone else who might be able to help).

    I’m currently working on designing some iPhone apps to be used as part of a sleep study, recording the sleeping habits and patterns of children. I’m keen to try to be as sensitive as possible to the fact that using a mobile device at night will expose the parent/guardian/carer who is recording the child’s sleep to blue light that will affect their own sleep.

    We’re looking into using the OS to intelligently understand (from the internal clock) when it is evening/night/daytime and to adjust the screen brightness automatically. We are also looking at designing the interface in a way that is sympathetic to night-time use and I wondered if you had any information on whether or not using ‘warm’ colours on dark backgrounds can go some way to reducing the amount of blue light produced?

    Any help/pointers to resources greatly appreciated.

    • The only “safe” way is to put a blue-blocking filter on the OUTside. In my opinion, ALL manufactures of electronic devises ought to be selling their products with a night-friendly blue-blocking film that can be either left on 24/7 or removed at the owners discretion during the daytime… PLUS a warning that using these devises at night can be harmful without the film. If they don’t do this voluntarily, maybe a class-action lawsuit might get their attention.

  73. I use the Solar Shield sunglasses mentioned in the article when I work on the computer at night. I have found them very effective in shutting out the blue light and allowing me to fall asleep in a reasonable time after I finish on the computer and go to bed. I recommend them. They are available on Amazon for around $17.00

  74. I have just bought a large digit blue LED alarm clock for my bedroom as I have trouble at night seeing the digits on my clock at night!

    Should I get rid of it?

  75. I have not used amber goggles but seems like a good idea to prevent the risks incured by melatonin suppression. I just saw an advert on aljazeera america of jindue goggles. …said to improve sleep, reduces under eye bags and wrinkles….but use acupuncture as basis of the technology. Do u think these too will protect us from blue light as uvex goggles do?

  76. I work nights and am looking for anything that will help me get adequate sleep during the day. Would these be useful for me and if so what is the best way to use them: wear them while I am working at night or put them on when I leave work right before I go to sleep (during which time it is already light outside)? I guess I’m not sure if the body actually stores the melatonin until it is needed or if it needs to be produced immediately before/while it is being used.

    • Hi Astra, I know this is a lot to consider, but please know that the World Health Organization’s International Agency for Research on Cancer warnings are well-established since 2007 that “shiftwork that involves circadian disruption is probably carcinogenic to humans” with significantly higher breast cancer rates. AMA came out with its own strong warnings in 2009 and 2012. I am angered that rarely do employers share this information with people who they hire to work the late shift. . . nor compensate them for it… nor offer any support training as to how minimize their risks. An extensive nurses research study was the first to prove the risks of circadian disruption… and it’s not even included in the nurses training curriculum. Perhaps OSHA can force employers to be honest with their employees who work the night shift. It’s no different than having an employee work with silica or asbestos without warning, training, and compensation. They are possibly worried about lawsuits (and they should be). Danish women have received financial compensation. If you can, please consider giving up the late shift. However, many people expose themselves to the same conditions voluntarily at home by sleeping with the TV and computers on… streetlights filtering in through moderately thin bedroom curtains… using white light night lights or bathroom lights at night. This is all so avoidable. It is so sad that needless, preventable harm is done to children and adults. Please speak up and share what you know. Demand that streetlights stop trespassing through your bedroom windows. We shouldn’t have to give up a night breeze through screened windows because we have to use black-out curtains instead.

    • Hi Astra, I know this is a lot to consider, but please know that the World Health Organization’s International Agency for Research on Cancer warnings are well-established since 2007 that “shiftwork that involves circadian disruption is probably carcinogenic to humans” with significantly higher breast cancer rates. AMA came out with its own strong warnings in 2009 and 2012. I am angered that rarely do employers share this information with people who they hire to work the late shift. . . nor compensate them for it… nor offer any support training as to how minimize their risks. An extensive nurses research study was the first to prove the risks of circadian disruption… and it’s not even included in the nurses training curriculum. Perhaps OSHA can force employers to be honest with their employees who work the night shift. It’s no different than having an employee work with silica or asbestos without warning, training, and compensation. They are possibly worried about lawsuits (and they should be). Danish women have received financial compensation. If you can, please consider giving up the late shift. However, many people expose themselves to the same conditions voluntarily at home by sleeping with the TV and computers on… streetlights filtering in through moderately thin bedroom curtains… using white light night lights or bathroom lights at night. This is all so avoidable. It is so sad that needless, preventable harm is done to children and adults. Please speak up and share what you know. Demand that streetlights stop trespassing through your bedroom windows. We shouldn’t have to give up a night breeze through screened windows because we have to use black-out curtains instead. btw, the latest trend to switchover municipal lighting to bright white/ high blue spectrum streetlights. We should fight-like-hell to stop this. Blue-rich (bright white) light should be banned for outdoor use at night in the public way, because it is harmful to humans and the environment.

  77. Since last time I checked this thread f.lux (for PC) has been updated and now has 2 settings below 1900k/Candle and 1200k/Ember.. By choosing one of these settings are you still getting some of the high blue spectrum or have you eliminated it? Or in other words – will the setting 1200k be as effective as a pair of goggles?

    • You’re referring to “color temperature” — the appearance of the light. A very warm reddish color temperature still contains the blue spike that drives fluorescence.

      Some people assume rather than check — there’s even some published research out there on light and sleep that uses f.lux without measuring the spectrum, taking their advertising as though it were true. But the f.lux people aren’t giving measurements of the spectrum, they’re talking color temperature. Actual check of the blue content would have to be taken from your own monitor.

      See prior mentions for some links.

  78. AJ: Blue items looks dark gray thru my red laser goggles.

    Laser goggles are overkill, in that they act like sunglasses.

    If I had to buy another pair of red googles, I would get laser pointer goggles

    Those would probably not filter out the light, like sunglasses do.

  79. What color should the blues be when looking through blue light blocking glasses, when watching TV or looking at a blue sky? I have a couple of pairs of amber lens glasses, (“Eagle Eyes’, as seen on TV, and sunglasses by Serrengetti).

    With the “Eagle Eyes”, all the blues still appear to be blue. With the Serrengetti, some light blues are green, while most darker blues and sky are still some shade of blue. I heard somewhere on an interview with D. Hansler that the blues should be green when wearing these glasses.

    Anybody notice this with other manufacturers, and is this a good test for determining how good the blue blocking capabilities really are?

  80. Any comment about the quality of the cheaper Solar Shields to the $80 ambers at blockbluelight? I’ve been wearing the Solar Shields and they seem to work.

  81. I just installed a screen protector on my Kindle that claims it helps block blue light. I am wondering if anyone has information that supports this? I am desperate for a quality night of sleep…and a little addicted to using certain apps before bed. Am I just going to have to suck it up and curb my screen time?

    I have suffered from chronic insomnia for most of my life…well before any of the common blue light issues came to be.

    Thank you all for the information…good food for thought.

    • The orange screen filters are usually very good, but you need to remove any ambient light and you can’t even turn on a regular light bulb for the rest of the night once you start using them with the lights turned off — doing so would just suppress the circadian rhythm again. So, the glasses are just easier.

      In any case a lot of insomnia (not all) can be caused by blood sugar issues, which can trigger cortisol swings. And one of the best and easiest to improve blood sugar swings and poor sleep is with resistant starch.

      It can’t hurt to try it. Do a Google search for “resistant starch for newbies” and you’ll get a good primer on it.

    • Kris, Remember this: Sunny MORNINGS are as important as dark NIGHTS. Do your best to curb night time use of tv and computers. Do yourself a favor and thrive in Dark-dark nights, and BRIGHT sunny mornings. That critical contrast is loved best by your circadian rhythm, which triggers and re-sets the clock of every single cell in your body. Get outside in the morning and suck up the blue light. Eat breakfast in a sunny room. (If it’s not sunny, OPEN YOUR COMPUTER-and absorb the computer’s blue light output.) Use only dim red or amber night lights.
      (also, Avoid late night snacks that contain linoleic acid, which feed cancer tumors.) Suggestion: use your bedroom for bedtime uses only . Get’s your mind in the right place, at the right time. : )

    • Kris A, have you had your vitamin D levels checked lately? I recently discovered that when I stop taking my D, I don’t sleep well and eventually get very depressed. This made me start researching D and I’ve been blown away by what I read about the vitamin D connection. Here are a few links:

      Here’s a 15-minute segment of video by that doctor that’s very interesting:

      Vitamin D is better than the flu shot (includes charts of ailments related to deficiency):

      And if you’re worried about toxicity (those comments are usually the first thing I hear when I mention D), read this:

      Tons more on the Internet! However, I’ll also mention that magnesium is great for sleep, and for a lot of other things. It’s another extremely important nutrient that most people are deficient in. Reading the magnesium chapter in the Eades’ book “Protein Power Lifeplan” convinced me that I should never be without it!

      Tryptophan works well–I used to use it occcasionally–and I prefer it to melatonin. Actually, I don’t take melatonin any more because I have Hashimoto’s and we’re not supposed to use it…can’t remember why.

      And lastly, I’ve discovered that recently, my sleep problems were related to adrenal issues, and using various adrenal support products has helped immensely. The one I discovered recently that was almost an instant cure is called ADRENergize and you can get it on Amazon and elsewhere. Although “energize” is in the name, don’t worry, it doesn’t energize you, just supports the adrenals so you don’t overproduce cortisol at night…or whatever my body was doing! I got such good sleep while using it, but then became concerned about the cost (I’d paid a lot more at the health food store before I found it online) so I started trying an herbal product, but nothing has worked like this. I’m starting it again today.

      Someone commented that when you take it daily, you should skip the weekends to avoid having your adrenal system become dependent on it. Sounds like a good idea…

      Obviously this is just information I’ve gathered online, so do your own research and consult your own experts!

  82. Once reading about how blue lights affects melatonin production, I immediately started with shutting off all lights and electronic equipment 3 hours before bedtime. I’d sit up with only stearin candles and read. I did this for a few days in a row. Even the first night and day I noticed an enormous difference in sleep quality and energy. I got my Amber glasses after a few days of doing this and switched to using only Amber. Although they help, they had nowhere near the effect that switching off all lights had.

  83. Hi Chris K,
    I just went looking for a pair of the Solar Shield amber-lensed goggles on Amazon after reading your article. They are showing as currently unavailable and add that they don’t know when or if this item will be back in stock. Could you recommend any other amber-lensed wraparounds designed for eyeglass wearers that would be comparable to these ones in both quality and price.
    Thanks, Peter

  84. Been doing some more research.

    According to my research, green light will affect the melatonin levels at half rate, that blue light does.

    Which means one would have to filter out the green light too.

    Amber filters let in more green light then orange filters. Either of these let in some green light.

    For light bulbs, the only bulb that does not have blue or green light is red light bulbs.

  85. Thank you for this informative article. I’ve been working nights for years, and I’ve no plans to alter my nocturnal schedule. I have however developed a severe vitamin D deficiency and can’t tolerate the house lights during the day/which is my night.
    I am in the process of putting a full spectrum grow light bulb in one of the fixtures in my bathroom to help me wake up at 4pm, and also increase my exposure to UV rays slightly to activate vitamin D. I was considering taking this a step further, and replacing other light bulbs with an artificial light that would mimic night time.
    Obviously the blue light being on the short spectrum, using movie magic and special effects blue blubs would be counter productive. Any suggestions on bulbs? Or is this too bizarre of an idea? I suppose I could use the amber glasses when walking around my house, but I’m looking for supplemental solutions. Thanks.

    • Night Nurse Ro, be aware that full-spectrum lights don’t contain UVB, which is the only light that produces Vitamin D. Sperti is the only manufacturer that I have found (or KBD is their other name, I think) of Vitamin D-producing lamps that are recognized by the FDA as proving their claims. However, exposing yourself to bright full-spectrum lights, if sunshine is not available, is still important during your “morning” to help with circadian rhythms. Vitamin D production and circadian rhythm adjustment are related but separate issues. I’m considering getting a Sperti lamp myself. They’re $425 plus shipping. The company makes other models that are cheaper, but this is specifically the Vitamin D-producing lamp. Learn more at or read The Vitamin D Solution, by Dr. Holick, the leading expert on Vitamin D. Excellent book all about Vitamin D (just don’t listen to his opinions on fat; he’s outdated on that issue). Best wishes.

  86. First question: what about television – is there anything that can be done to adjust the light it emits? Second question: Does anyone use bright light therapy in the morning to also promote phase shifting of circadian rhythm or sleep cycle?

  87. Does anyone know: I read that the red lights are good at night too, so I bought a bunch and really like them… Are they as good as Amber light?

  88. Hi all sorry if this might sound as a silly question… Does the light exposure also affect the production of melanin (not melatonin) I mean that one that pigments our hair?

  89. Is it simply the amber color of the lens that blocks the blue light? or is there more to it than that?

    I’ve read through all posts above and didn’t see an answer to this question, can someone please help shed some light?

    I already own a pair of oakley glasses that have orange color lenses and they’re really old so I don’t know if they technically block blue light or not. I think they maybe safety glasses too as the lens is one big piece. Can I achieve the same effect as the UVEX glasses with my orange oakleys or any glasses with an orange lens?

    thanks in advance for any help!

    • Hi Ethan,
      My hubby & I each bought amber glasses from and are happy with them. They are perfect for the application and worth the price. There are a couple interviews on the website that explain the science behind the glasses and the effort to avoid blue light at night (unless you are working the night shift). There is a phone number that you can even call for additional information. Plus there is a money-back guarantee. Although I have loaned my glasses out before (to a cancer patient just until he got his own), i would never dream of returning mine. These glasses will not help a person who permanently lost their ability to produce melatonin… for a variety of reasons. Remember, bright light –sun light & blue light– during the DAY is essential… and just as important as the need for darkness & avoiding blue light at NIGHT. (amber night light is OK)

  90. Great article! I have truly enjoyed reading all the comments as well. I did a google search on the overuse of otc melatonin, and this popped up. I’m thankful for that. I plan to incorporate several suggestions from this article to gain hold of a better night’s sleep. God Bless you all!

  91. I tried the amber goggles Chris recommended but they felt strange to me. I think I have found the solution though. On a recent trip to Japan, a Japanese friend told me about the eyeglass chain JINS, which sells glasses specifically designed to reduce eyestrain. They cut 50% of the blue light while letting in 85% percent of the regular light. So it’s not as severe as the amber ones and thus probably not as effective, but they look like regular glasses and I am hardly aware of the pale amber tint. I think this is a good compromise. Here is the page for them, in Japanese

  92. Hi Chris, I mentioned to my eye doctor that I have been using blue-blocking glasses for the past couple of weeks and she warned me not to use lenses that are popularly sold directly to the public, citing some research she had recently seen at a conference, stating that some of these cheaper products may in fact cause some other eye damage. She didn’t have the study handy, but I’ve been looking for it in order to find out if this is valid, or if it’s an industry ploy to get people to buy the more expensive lenses from their eye dr. Have you heard anything at all about this? I can’t find any info on it. Thx.

  93. Hi There

    I have been suffering with really bad insomnia for a while now and it is really starting to make me feel poorly. I am 63 and enjoy writing but during the day I have lost all my concentration. I have sent for a pair of the glasses and I am praying they are going to work. I have tried melatonin tablets but no luck with them. I will keep you all posted. If they can help me then they must surely work.

  94. Does anyone know if the Amazon Kindle PAPERLIGHT stop melatonin production? I have been considering getting one and wanted to hear some opinions from users before I end up getting another device that disrupts my sleep.

    • Hi Mitch, If you use any electronic devises that emit any type of light (other than very dim amber or red) it is best to also use glasses that block out all emitted blue light. I use amber-colored glasses purchased at On the website, there is also an interview that is well-worth the time to listen to that explains in layman’s terms how light can interrupt melatonin production, and why this is a serious matter. I have studied this for years, and find this fascinating and alarming as to WHY it takes so much TIME to get the word out. So many people suffer needlessly. The bottom line is, your body needs dark-dark nights and bright-bright days. Your body senses this change through the retina, and this signal is sent to every internal cell within your body. Researchers discovered individual cells actually have a critically important circadian cycle. However, since the initial signal comes through the retina, blue-blocking glasses and sleeping masks are effective at night. Remember the other important part of the equation is BRIGHT, bright daylight. also see research by Drs David Blask, Stevens,George Brainard (Bud)

      • Audrey,
        Thank you for the quick reply & tips. I will def order a pair of those glasses to try out. I travel quite a bit and sometimes on the go it’s hard to bring everything along with you. I know the amazon kindle original ereader is not a backlit device. You do need an additional light to read it, just as you would a book. I was told there are apps for example that can print these articles to an epub or pdf format so you can later read these posts from Chris Kresser and others on the Kindle(with modified firmware)

        That is what I’m looking to do because I spend too much time on a computer.With a device as small as the Kindle, one could read it laying down, instead of a laptop which is a hotter heavier etc. The paperlight is supposed to have some special glow tech, which in theory does not project light to your face. So wondering if that would be ok to use without glasses before I plunk down $$.

    • Mitch,

      I don’t know if the Kindle Paperwhite interferes with melatonin production – but I have found it works really well for me to read on it at night. Just turn the brightness all the way down and increase the font so you can still read. The screen becomes really dim. Reading a classic before bed really helps me to relax. I have tried reading hard copy books with different book lights – but I didn’t like how bright the book lights were. The PaperWhite sure works for me.

  95. Chris, This thread has been going on for a while. Great topic. When I sailed at night, we used red lights in the boat cabin and bathroom to keep our night vision. I think those red lights made me drowsy! (Or was it the motion sickness?!)

    I like the NASA blue light therapy to tease the body into the circadian rhythm. Maybe the other secret is to get the right kind of light (sunlight?) during the right time of day.

    Ohhh, evolution. The digital native generation is too young to have evolved past it. What’s next for human-sleep?

  96. Thanks so much for this article. Will be trying the glasses/goggles and f-lux. Need to find some way to cause better sleep as the “waking up” during night due to cortisol/adrenals/Hashimoto’s is obviously impacting my waking moments. Thank you once again for providing very useful information.

  97. Hi. Wraparounds over glasses are ok at home, but are there prescription amber wraparound glasses to wear out of the house at night?

    My optometrist said they they can get “Cocoon” prescription wraparound product, and they have a catalog. Anyone know about those?

    He mentioned something about polarization in addition to the amber. Would polarization be good, bad or indifferent?

    Also, there seem to be loads of Solar Shield clip-ons on ebay. Would those help even though they’re not wrap-around?


    • Oral melatonin dosing can be highly variable from one person to the next and the timing of the dose is crucial as taking it at the wrong time can reset the internal clock and promote insomnia when you want to sleep.

      The glasses are just a return to pre-electric lighting as far as the body is concerned. Far safer and cheaper.

  98. this is good articles. when i was a kid, i don’t know why do i have to turn off the lights at night even my laptop. the explanation is easy to understand. thank you

  99. For anyone who is interested, I bought the expensive amber glasses available from and they do appear to block more blue light than the Uvex $8 glasses. The more expensive lens is clearer and of a higher quality.

    I think the Uvex glasses are perfectly fine (they do block most of the blue light), but I can definitely say that the lowbluelights glasses block even more blue light. The company also offers a 30-day money back guarantee.

    • Thanks Dan for the reassurance – I just bought the $70 Low Blue Light glasses and was wondering if I should have gotten the the $10 Uvex glasses instead.

  100. Hi Chris,

    Another fantastic article.
    Quick question: Does these glasses also inhibit the blue light emission?
    “Uvex 9176-020 x-act Amber safety specs with amber lens”

  101. I first read about the following from the book ‘Lights Out’ by T.S. Wiley and Bent Formby, Ph. D., then Googled it:
    “The circadian clock times a wide range of behavioral and bodily functions by controlling temperature and the release of hormones. And until now it has been widely believed that it is set by daily and seasonal changes in the light that enters through the eyes.

    “But our results challenge this belief. The study demonstrates that circadian rhythms in humans can be altered simply by shining light on the backs of people’s knees,” says Dr. Scott Campbell, director of the Laboratory of Human Chronobiology at Cornell University Medical College in White Plains, New York.

    Writing in the journal Science, Campbell and colleague Dr. Patricia Murphy describe an experiment in which volunteers agreed to spend four days at their laboratory in a dimly lit suite. Periodically, they sat in a reclining chair while the backs of their knees were exposed to bright light delivered through a fiber-optic pad in a housing strapped to their legs. The pad was adapted from those used to treat infants born with neonatal jaundice. None of the volunteers knew exactly when the light source was switched on.

    The knee was chosen as the site of the experiment because it was far from the eye, therefore minimizing any risk that light shown would enter the subject’s eye.

    The researchers noted that the light exposure on the back of the knee was associated with shifts in the timing of body temperature changes and in the release of the hormone melatonin from the pineal gland, located deep in the brain. ”

    Makes me wonder if the glasses are enough to make a difference then, if what they found above is true, that the skin is also light sensitive?

  102. I do a lot of late night design work on the computer and find that ever since I used f.lux I definitely sleep better. I need my room to be dark when I sleep so I dimmed and blacked out my cable box and router lights with Dimmys which work wonderfully.

  103. I started wearing blue blocking glasses a few months ago and it did the trick for my insomnia. I immediately had trouble sleeping after installing energy saving LED lights around the house. The blue blocks made all the difference. At first I used a pair of darkened blue block sunglasses I happened to already have. I’ve since bought the pair Chris recommends on Amazon and they’re great. …A very economical solution to my sleepless nights.

  104. Hi!,
    I have what you call Insomnia quite frequently and so I ‘ve discovered that Polaroid Sunglasses are ideal for my sleep at night. I’m not sayimg this will work for everyone but, It’s a real good way of limiting the light in your bedroom at night. Put your sunglasses on 1 hour before going to bed.
    Thanks for reading about my idea, hope this helps.

  105. Check out this great book by T. S. Wiley “Lights Out” she goes into great depth about the importance of sleep, and the how and why lack of sleep (especially in complete darkness) can be detrimental to your health.

  106. I know I’m very sensitive to light – I get headaches & sore eyes if I sit in artificial light in the daytime, & I’ve gone to some trouble to make sure I get natural daylight or blue light… I’ve been aware of the desirability of darkness at night for sleep, & have used f.lux on my computer for some time now, as well as using only a flashlight if I get up in the night. But I didn’t know about the amber goggles -I’ll definitely check them out. Maybe it will help me sleep through the night properly.

  107. When I feel sleepy, I get ready for bed (turn of lights, clean teeth etc). By the time I’m in bed I’m wide awake – very alert. I then can’t sleep for hours, and my room is very dark. Even if I keep the yellow tinted glasses on the whole time, it makes no difference. I wondered weather the walking around getting ready for bed, maybe even using the noisy electric touchbrush, is giving off other hormones telling me to wake up… As an experiment, one night I just went straight to bed without “getting ready for bed”, not even changing my clothes, and I found that I fell asleep really quickly. Maybe light is just one part of the puzzle…

    • Electric toothbrushes reportedly radiate huge amounts of EMF’s to the brain. This artificial energy may stimulate some area of your brain, which then contributes to keeping you awake?

      • “Electric toothbrushes reportedly radiate huge amounts of EMF’s to the brain” no there is not radiat any huge amount of emf dont spread myth,
        “. This artificial energy may stimulate some area of your brain, which then contributes to keeping you awake?” there was some studies showing that emf can lower melatonin lvl but many more with better methodology dont find such assocation.

  108. Thanks Dan & Audrey 🙂 I think I will give the screen filter a try! I am curious to test this for a period of time – I have always wondered why I have problems falling asleep and often wake up feeling beat up – I eat pretty healthy, exercise, meditate and have very little daily stress – so I’m thinking maybe this will have an effect – and if it doesn’t I guess tried most anyway:)

    • Low-blue lighting/filters are a great start for encouraging melatonin production and stopping evening cortisol. And you may notice that playing with low-blue lighting alone is all you need to reset your body.

      However, if you find that low-blue lighting isn’t enough to get your evening cortisol down you should consider trying HeartMath® (specifically their “Heart Lock” technique with any of their heart monitoring devices) while listening to relaxing music right before bed. After a few weeks of that pre-bedtime routine, your evening cortisol should normalize, if you are generally healthy. I believe Kresser recommends the “Rest Assured” sleep CDs — which is another natural approach to reducing evening cortisol. Good luck!

  109. Hi Nik, There is nothing you can do at night via computer settings or software that will eliminate enough of the blue wavelengths emitted from your computer monitor and still allow the user a maximum natural melatonin production. Using a filter over your screen (assuming an especially dark room) or wearing the glasses that filter out all the blue are the best options other than NOT using the computer at night. Personally, I am trying my best to reduce computer use at night, and starting my day earlier. In the morning, the blue light emitted from the computer is actually an advantage, and helps wake me up!

  110. Thanks Dan! Nice that it can go down to 2300K on the Mac.. That would be ok I guess.. And then no lightbulbs… Does anybody know another program that can go that low on a PC?

    I have a pair of glasses but they are just too annoying for me. So I would rather make my surrounding light dimmed. On my monitor I can go into the settings and adjust red/green/blue – I guess I could just turn the blue all the way down??

    • Audrey is correct. There is really nothing you can do to any monitor to get it below 2000ºK. Keep in mind that the morning is sunrise is around 2000ºK, so you really need to be warmer than 2000ºK to encourage melatonin production

      If you think about it, we evolved to wake at sunrise (i.e. when light becomes cooler than 2000ºK) — which causes our bodies to suppress melatonin and increase cortisol as part of our circadian rhythm. So, sitting in a dark room with a 2300ºK monitor won’t do you very much good in the long run — it would be like trying to get ready for sleep while staring at an early morning/dawn sun. It’s certainly better than sitting in a room with 3600ºK lamps, but your melatonin will still be suppressed.

      If you don’t like the glasses, your best bet are the low-blue monitor filters from Not much more you can do beyond that.

  111. I have f.lux on my computer – but the lowest setting 3400K – isn’t that still too high?? Wouldn’t around 2000K be better?? Is there a program out there which can go lower? Or would manually lowering the blue light on your monitor be the solution?

    • f.lux on the Mac can get down to 2300ºK. They call it “candle” setting, but in reality a candle is actually around 1800ºK. Anything below 2000ºK would be ideal — but f.lux cannot make your monitor that warm.

      f.lux is really intended to mimic your ambient light, whatever that may be (halogen, tungsten, etc). The idea is to have your monitor mimic the effect of reading a book under your lights. Keep in mind that even if your monitor were 1800ºK and your lights were 3600ºK, your melatonin will still be suppressed by the 3600ºK lightbulbs.

      In any case, sells plastic monitor filters that will filter out all blue wavelengths. You just press them down on top of your iPad, iPhone or computer monitor. They even sell them for your TV.

      However, in my opinion, nothing beats the glasses — since they filter out all blue light for you.

  112. In your article, the word “f.lux” was a link to this website where you can download the program
    for free. I wanted to check in first and make sure this is the legit
    website for that download. Would you please provide some links
    that you know are safe? Thank you.

  113. I bought this motion sensor night light at Walmart after reading Lights Out: Sugar, Sleep and Survival by Wiley several months ago. — — The light is a dim white light, but my room remains dark until I wave my hand and the light goes on in the bathroom for me to take a bio-break. Wiley seems to have some controversy because of her interview with Lynn Sherr on ABC, but her book seemed to make sense. She said taking melatonin shrinks the pineal gland. I believe Robb Wolf recommended sleeping at a temperature no higher than 70 degrees. I like to use the sleep/eye mask that is contoured so the fabric doesn’t touch my eyes; it feels kind of spongey and I found them at TJ Max, but looks similar to this one on Amazon without the nose piece — ( — I also covered the light on my smoke alarm with several layers of blue paint tape (so it doesn’t get tacky) and I bought a spring rod shower curtain (inexpensive at Big Lots) to place black out curtains (from Bed, Bath and Beyond) in my window as I have a vertical window treatment outside the window opening. My TV has to be shut completely down at the surge protector because of the red sensor light and it is behind armoire doors. Additionally, I started wearing ear plugs so I can listen to my breathing to try to shut off my brain (mostly singing songs, not stressful stuff). Like J.W. Simpkins comment above, I am starting the epsom salt baths too (inexpensive at Big Lots). By the way, his suggestion on the cat suit gave me a belly laugh. Besides the sexy ones, there were some that looked like the men from the Big Bang Theory sitcom show would wear. With tv showing most of the shows on the computer including the news, I don’t have to put my tv on at night; I just watch them during the early evening or on the weekends.Thanx for the discussion and other book recommendations. I am ordering the Uvex goggles for not only me, but my children who are not sleeping well. My college child is overwhelmed with homework and stays on the computer until late.

    • Special glasses wouldn’t really do much. Warm light doesn’t technically trigger melatonin production — in reality it just doesn’t block it from being produced. So, you can have a bonfire on a sunny beach, but the bonfire won’t make you sleepy because even a small amount of cool sunlight is all you need to prevent melatonin during the day. The temperature of daylight is already perfect as it is — at least from an evolutionary standpoint — so there’s not really any need to toy with the light from the sun.

      There are special lights that people can use to establish circadian rhythm. The lights have some risks to the eyes (i.e. UV damage) but they can be very beneficial in places where sunlight is difficult to obtain at different times of the year. But, for most people, simply getting some sunlight into your house early in the morning is all you need to establish circadian rhythm.

  114. I’ve been using f.lux for about 2 years and it makes a humongous difference , especially if you work on your computer at night. There was one night I turned it off because my computer was running slow and I nearly was blinded at the light my computer was emitting! I just purchased the amber-lenses . I know they’ll be of great help.

  115. Chris,
    Just wanted to say thank you for the good information on the talk you gave with the Village Green Network yesterday. Very informative and helpful.

  116. Hi Chris, have you looked into the effect that sodium fluoride (which is in tap water amongst many other things) has on circadian rhythms and on the pineal gland/the production of melatonin? If so, I would be very interested to hear what you think about it.

  117. Last night I gave myself 2 hours in a room with a lamp plugged into a dimmer, dimmed so it looked orange, and a tv on movie picutre mode (not dynamic or standard), and all other little led’s covered in socks. I found myself randomly looking away from the tv to rest my eyes. At the end of it, I felt like I had taken a strong sleeping pill.

  118. How about the light receptors on our skin?
    Artifical light on skin after sundown messes with melatonin too. Is it best to cover up after sundown too? As well as the glasses??

    • Earlier in this thread, it was made clear that the one study that claimed that exposure of the skin to light suppressed melatonin production could never be replicated. The effect is entirely through the eyes. (We do need sunlight on our skin to produce vitamin D)

  119. Is there any way to adjust the focus on the Uvex orange safety glasses? I can’t focus on things close, like my phone or a smaller font on the computer.

    As long as you have a dimmer and your light isn’t LED, dimming it will make it more ‘orange’.

  120. Or… One can simply take 1mg of melatonin and be 100x ahead of the game. And not look like an imbecile wearing sunglasses indoors.

    Think about it.

    • 100x times ahead of the game? Oral melatonin dosing can be highly variable from one person to the next and the timing is crucial as taking it at the wrong time can reset the internal clock and promote insomnia when you want to sleep.

      The glasses are just a return to pre-electric lighting as far as the body is concerned. Far safer and cheaper.

  121. Any suggestions for those of us that work the graveyard shift? I work a 12.5 hour day with a crazy to explain schedule basically 4.5 days one week and 3.5 days the next and due to kids schedules I switch back to a “normal” schedule on my days off.

    • There is an entire chapter dedicated to a graveyard shift protocol for using the low-blue glasses in the book, “Great Sleep! Reduced Cancer!: A Scientific Approach to Great Sleep and Reduced Cancer Risk,” by Richard L. Hansler (

      The book is very cheap (less than $5) and it will walk you through the steps of using the glasses at the right time to create a circadian rhythm. Well worth the price.

    • Hi Jenn,
      It is important for you to know that in 2007, the World Health Organization degreed shift work as a probable carcinogen due to circadian disruption by artificial light at night disrupting their ability to produce melatonin.
      I believe that all businesses and institutions who employ shift workers ought to notify their employees of the health risks, pay them more because of these risks, and educate their shift-worker employees how to minimize their risks and train their circadian to produce melatonin naturally. Not to do so, would be similar to hiring employees to work with asbestos without adequate warnings and training. btw, Belgium employers have already begun monetary compensation for their cancer victims when linked to shift-work.

      • Fascinating. As a midwife, I am faced with unpredictable sleep disturbances, without any rhyme or reason whatsoever. I just do the best I can. I wonder now if this had to do with my nurslings’ poor sleep. Perhaps since my melatonin levels were deranged, theirs were too.

  122. I am so lucky that I sleep well, and always have, regardless of whether I use devices before bedtime or not.

    My question is though, my room is never dark due to street lights outside shining in my window all night. Could this ambient street light be affecting my melatonin production during sleep, and should I do something about?

    I guess in nature we would sleep in absolute darkness (except perhaps for fire light).

    If this is the case (even though we’re not necessarily aware of it, and still sleep well) would an eye ‘patch’ such as you get on airplanes, or blackout curtains, be a good idea?

    • Fire light does not affect melatonin production since the color temperature of firelight is less than (i.e. warmer) than sunrise. Oil lamp, candle and fire light are all warm (low blue) light (~1800ºK). Sunrise starts at 2000ºK and quickly increases by the minute to higher (bluer) color temperatures. So, melatonin is affected by color temperature and intensity. Your eyelids are purposefully thin so that you don’t miss the blue light at sunrise when your eyes are closed.

      If you close your eyelids and can notice a significant difference in the amount of light when either you cover your eyes or you don’t, then it probably is affecting your melatonin. But, if it’s only a slight difference, then it probably won’t make that much of a difference. But, generally speaking, it depends on the color temperature and intensity of the light entering the room.

      • And just to clarify, color temperature in degrees Kelvin increases as your light becomes more blue and decreases in degrees Kelvin as it becomes more amber. Fire light is very “warm” (low blue) so it has a lower color temperature. Sunlight is “cooler” (high blue) so it has a higher color temperature in degrees Kelvin. It’s confusing, and somewhat backwards.

        To illustrate this, see this chart:

        The reason why electric lightbulbs suppress melatonin is because the “warmest” tungsten lightbulb you can get at Home Depot starts at 2,700ºK. Even a 60W bulb has too much blue light and is not low enough on the color temperature scale:

        A light bulb would need to be around 1,800ºK in order to replicate fire light — which does not suppress melatonin. And again, sunrise starts at 2,000ºK and quickly increases from there. sells lights that are very low color temperature and do not suppress melatonin — they are perfect for a nursery when mothers need to nurse and babies need to keep their melatonin flowing on a particular rhythm. It basically just simulates fire light. You know, the same light people have been using for millions of years up until electric lights were mass produced.

        Incidentally, the only intense blue light that our ancestors were exposed to at night would have been a full moon. And it’s no wonder that full moons were always associated with mischief and weird behavior. Perhaps it was from everyone’s melatonin being disrupted!

  123. I just installed f.lux on my laptop. Now my screen is orangey. But I’m going to try it. I hate any light in the room. My husband says I am a vampire. He likes to have light. I usually go to be before him and I try to make the room very dark. When he was away for a week, I was in heaving with a completely dark room. Maybe I should get a sleeping mask.

  124. Hi Chris – thanks so much for this article. I have had lots of trouble sleeping and so far the best remedies are limiting stress and not working after a certain point each night. The modern work life unfortunately seems to be a slow death by sitting and computer brain drain. I’ve tried f.lux but unfortunately it violates my work’s Internet security policy! I’m going to try the amber glasses because part of my daily de-stress routine involves TV episodes of Modern Family. A good laugh never hurt anyone.
    I do have a question for you though – when I have the opportunity to expose myself to sunlight should I not wear sunglasses in order to maximize exposure? Or is the potential damage to my eyes not worth the risk?
    I live in MN and during the winter I’ve avoided wearing sunglasses to maximize natural sunlight exposure unless it puts me at risk for a car accident. (Which is rare – seems the gray winter days are unending this year!)

    • Sarah,

      Sunglasses won’t make a difference in terms of vitamin D production, because it’s light hitting skin that matters. You should abstain from sunglasses for the first 20min or so however because your body’s natural sunblock chemicals are light-activated from your eyes. Putting them on after 20min will mean max skin and eye protection and continued vit D creation. I believe i read this in the book ‘survival of the sickest’.

      • Thanks for the information! I’m more concerned about the melatonin production than vitamin d. Since the vitamin d production to your point is done through light hitting skin – I have to supplement or hit the electric beach in the winter since the only skin I ever have exposed in the winter here is my nose. I doubt that will do much to help produce vitamin d! My trip to FL in the next month will help. It’s my understanding the melatonin production is stimulated through the light exposure in the eyes. That is why I’m questioning if I should always avoid sunglasses in the winter months to maximize the light exposure. But maybe it doesn’t matter? It would be a trade-off with melatonin production and crows feet around my eyes from squinting. : )

  125. I was wondering if you guys think regular blue-light blocking polarized sunglasses would be similarly effective as the Uvex brand – they block UV and blue it states, but also some percentage of the rest of the visible spectrum. Do you guys think normal sunglasses would block too much in a dark environment, such that a cheap blue-blocking only pair would be better for doing things at night?

  126. Interestingly, I find that using the Internet within an hour before bed, even with F.lux installed, the brightness turned all the way down, and orange goggles on, still disrupts my sleep–it takes longer to fall asleep, I wake up more easily and more often, and feel more groggy when I get up.

    I suspect that there is something uniquely stimulating, and thus sleep-disrupting, about using the Internet. The instant access to an endless supply of information, the surrogate social interaction, the visual and cognitive stimulation…all of this is highly discordant with the evolutionary environment, or even with the post-agricultural human environment prior to the 21st century.

    My sleep is of the highest quality when I strictly avoid using the computer at all after sundown. Reading a book, meditating, or playing/listening to music in low light (preferably candlelight) seems to work the best for improving my sleep, mood, and everything else.

    • For what it’s worth, I’ve noticed the same effect Brendan. I guess it shows that there’s rarely one “fix” for anything – life and our bodies are too complex for that.

      But of course everyone still looks for what “the” problem is! 🙂

    • You’re absolutely right, Brendan. I couldn’t have said it better: “I suspect that there is something uniquely stimulating, and thus sleep-disrupting, about using the Internet. The instant access to an endless supply of information, the surrogate social interaction, the visual and cognitive stimulation…”

      I intend to get the Uvex glasses mentioned, but the behavior has to change as well. When I go to bed late after being on the computer–for any reason–and I can’t sleep, I realize it’s because my mind has been so active. I’m either caught up in the story of a movie, or thinking about the email I’m composing, or absorbing new information when doing health research…and when the little wheels in my mind are spinning fast, they don’t just stop when I lie down, even if I’m not consciously thinking about any of those things. It’s the focused concentration. Maddening. I wish I could just flip a switch, but if I want to get good sleep, I’ll have to curtail my activities.

      • Being on the computer, iPad or the Kindle Fire at night is too stimulating for me as well. I now try to stop all electronics by 7 or 8 PM. The only exception is the Kindle Paperwhite – I read on this device and turn the brightness all the way down (increase the font) and read not too exciting books. I would rather read this way than with a hard copy book and a bright book light.

    • It’s not that – it’s that green light also disrupts melatonin production. Any frequency lower than yellow does. If you look through the scientific papers on color and melatonin, you’ll find a neat bell curve.

      From my personal experimentation, when I wear red laser-safety glasses that block any frequency up to 570nm (reddish-orange) with an optical density of more than 5 (i.e. 99.999% of the light is blocked), I can hang out on the Internet until the cows come home and still sleep like a baby. Orange goggles don’t work nearly as well.

    • Be REALLY grateful they will grow out of this. I have a 21 year old with autism who still keeps baby/toddler unpredictable hours, so….there are people out there who never get to move out of that stage of life. I’m replying half in jest, too, but sometimes a new perspective is uplifting. If you have a healthy kid, hold on tight with gratitude to the platitude “this, too, shall pass.”

    • Apply the information in this article that’s what you can do.

      I had three within 2 years – now one 3 and 18 month old twins. I figured out that light was an issue about 6 months in with the first child. They all sleep 10 – 11 hours a night now. Every night. I found orange and yellow light bulbs for lights in their rooms and instituted a “no screens” policy after supper. I turn lights out and keep lights very low after the sun goes down. I make certain to give the babies their night feeding in a pitch black room. On the odd occasion when they would wake up, or when they were doing night feedings I made sure there was almost no light, and what there was had no blue. You can’t read with a red light very well (with most children’s books) but it works great for a feeding/changing light in the middle of the night. BTW Lowe’s has different colors of CFD bulbs – red, orange, and yellow seem to work great.

      There are other behavioral things we did as well, but light has been a critical factor for my family’s sleep and health.


      Multiple sources recommend using low/no-blue light to help your baby sleep (and to help the adult, who gets up in the night, not to disrupt his/her sleep, as well).

      That’s another reason we put amber-coated bulbs in the refrigerator! See above and links for more recommendations. Once you understand how “white” fluorescent/LED light regulates sleepiness, you will find it easy enough to eliminate that — and you can get around just fine with amber or red nightlights.

      There’s one big commercial company selling a very bright low-blue bulb now:

      I bought one — won’t buy more as they’re way too expensive and too bright for nighttime use, but the single one is plenty to illuminate a whole room in the early evening for activities like sewing where matching colors accurately counts a lot.

  127. Chris, usually I take a shower at night before bed. It would be hard to wear those glasses in the shower. Maybe I should take the shower earlier perhaps at 7pm so wearing the glasses is not needed at that time? How do you handle this?

    • Dimmer switch in bathroom helps a lot with this. I usually shower late at night, and I would get no sleep if I did it in standard bathroom lighting. Put dimmers on all bathroom (overhead/vanity) light switches and this will help some. I keep it almost fully dark in there–just enough light to find the soap and the towel afterward.

    • As one reader mentioned earlier – use one electric candle in the bathroom. It gives off a warm yellow glow and is enough light to be able to shower, brush teeth, etc.

  128. LOL… One night I was adjusting the TV color, contrast, etc while wearing my Uvex glasses. Ummmmm, didn’t look too good the next day. 😉 I don’t recommend that.

    I did buy a pair of nice looking frames from my eye doctor (that fit me almost three years ago with Ortho-K lenses I wear while sleeping/take out next morning and can see all day!) with the blue-blocking lenses in them and use those, especially when out after dark and don’t want to look like a complete dork with the Uvex glasses. Though I did go to Costco one night and wore them. I was kind of disappointed that no one looked at me strangely The other frames do fit/feel better than the Uvex pair. I hope they are as effective. The optician seemed to think they would be, but I have my doubts. I figure they are better than nothing.

    Well written post, Chris, that needs to be shared. I’ll do just that!

  129. I use Gunnars lenses and love them but I don’t remember to use them all the time. Seems easier to just get off the computer at a set time every night.

  130. I use the uvex glasses. They work great, however, I have to lift them from my eyes a lot to get a clear view of what I’m doing while cooking. Some things, like food doneness are hard to decipher.

  131. I’ve been using f.lux, a nearly completely dark bedroom, electronic candles with timers and red light bulbs for quite a while now and got great results with those.

    I recently added the amber glasses and they made a noticeable difference as well as tv watching was one issue that all of the other items did not address. Now I’ll find myself getting sleepy and yawning while watching tv. On the nights I forget to wear the amber glasses I’ll be wide awake until I turn off the tv.

    A completely dark bedroom was a big help but I found that cracking the window shade just a few inches allowed enough natural light in in the morning to help wake me up. Otherwise I had a tendency to just keep sleeping.

    The electronic candles are great. They give off a warm yellow/orange/red glow and allow me to turn off all of the regular lights in my house at night. Most are set to come on automatically at 6pm each night and turn off at 11pm when I head to bed. I keep an additional one in the bedroom that runs from 11pm till 4am in case I need to get up during the night. Completely dark is wonderful but can be a pain for shins and toes if you need to get up.

    • I agree with the electronic candles – I just put one in the hallway, the bedroom and the bathroom. They give off just enough light to see and the warm glow is calming.

  132. Hey Chris!
    Great article, definitely will “share” it on fb. In regards to melatonin production, bluelight and goggles: is blue light entering through the eye the major factor in melatonin? I like the idea of having those amber lenses (and already use f.lux) but I’m curious about blue light hitting the skin…does that have an effect, if any?


    • I looked into it a bit further this afternoon, and light hitting the skin does, in fact, impact melatonin as David suggested. I am getting the full-text of a study that showed that transdermal light applied at the knee suppresses melatonin.

      • Thanks very much for looking into that more Chris – really interesting area!

        All credit to Robb W though – I just soak up the information from his podcasts (and yours!).

      • The study was likely flawed as it was never reproduced by anyone, ever.

        The original study:

        If the skin was that sensitive, the study should have been easily replicated. But, to this day, nobody has been able to do it.

        More likely the pulsing light behind the knee triggered another melatonin suppressor that had nothing to do with light. For instance, melatonin can be suppressed by sound (i.e. your alarm clock), but light just happens to be a stronger influence than your other senses. For all we know, the pulsing light had a slight static charge or infrared heat pulse that affected melatonin.

        And, besides, there is far more evidence out there to suggest that light on skin does NOT suppress melatonin:

            • Dan sent me a study suggesting that light stimulation on the skin is sufficient to suppress melatonin. I haven’t read the full-text yet, and maybe Dan can weigh in here, but I suspect the effect is considerably less than bright light on the retina.

              • Slightly confused – I assumed that Dan was only referencing studies which showed that melatonin production was not affected by light on the skin.

                Since you know Robb W well Chris – I wonder if you have time to ask him what it was that I have a fuzzy memory of him talking about?

                For what it’s worth, I agree that intuitively the retina is what mainly drives this. I’m just curious to know what the evidence is for the effect of light on skin.

                Thanks for taking the time!

                • That’s the Campbell and Murphy study I was referring to, that nobody has been able to reproduce. I believe they used a biliblanket under the knees and supposedly suppressed melatonin.

                  What I’m saying is that the Campbell and Murphy study is likely flawed since nobody else on the planet has been able to reproduce it.

                  If skin was that sensitive to melatonin, the results should have been easy to reproduce. No such luck however. It was a fluke.

                  My sense is that melatonin in the Campbell and Murphy study was suppressed by an exogenous factor — such as heat, sound, static charge, etc. and the researchers just wrongly assumed that it was the biliblanket.

                  And even if Campbell and Murphy discovered something (high doubtful, since it can’t be reproduced) the study is pretty useless for real world applications since nobody sleeps with a biliblanket under their kneecaps. 🙂

              • I was just thinking back to watching movies set in older times when wearing full pajamas at night was common. I wonder if this was the reason why. Is fabric covering the skin enough to block the light?

  133. I installed f.lux, but usually when I am working late, I’m handling color sensitive materials on the computer, so I usually just turn it off. The moral of this story is: don’t work on digital art late at night.

  134. I have f.lux on my computer, and while I’m sure it helps somewhat, even if I have the brightness turned all the way down I sleep poorly if I use my computer within an hour of bedtime. I have a pair of the UVEX glasses, and with those I can continue working on my computer with no ill effects on my sleep. The UVEX glasses are very good and quite cheap ($9).

    The effects of those glasses on melatonin suppression is remarkable– they completely block the effect.

    • I’ve noticed the same thing when I use the Solar Shield brand. I was up until 1 AM doing work the other night and fell asleep nearly immediately when I finally got to bed, thanks to the goggles. Normally I’d be tossing and turning and totally amped up from all the light exposure. (Now if I can just find a way to get all my work done at a more reasonable hour…)

      • I don’t mind looking strange, but I found those glasses completely unworkable. They made everything fuzzy and did not fit well over my glasses. I may try the more expensive brand.

    • The lense quality of those things has to be terribl for $9. Cheap sunglasses hurt my eyes and I think I’ve read have negative effects with long term use. Although I think that had something to do with tricking your eyes into letting too much light in…. anyways one more thing to worry about. Damaging vision by looking through cheap lenses for hours each day.

  135. Another option is changing the colour of your artificial lights. This is now possible (yet still costly) with new LED lighting. However, costs are dropping significantly every year.

    disclaimer: I work for philips lighting, but not for the division that makes this product>

  136. I purchased some glasses about a month or so ago. I love them. I do wear them daily because while I have never had issues falling asleep (or even staying) my sleep can get pretty screwy if I’m not careful. I’m high strung – not like I used to be thanks to Primal. I put them on and I can feel my eyes relax – I take them and they start to “tighten” up again. And within an hour I’m feeling pretty sleepy.

  137. Chris, this is not about artificial light wrecking sleep but is about sleep wrecking no less. Maybe you could address it in an article at some point. As the parent of a 3 year old and a new baby, I wonder now more than ever…what are the long term effects of sleep deprivation for an entire year for each child on the parent? I am breastfeeding a year as I did with my first. Of course in the beginning the sleep is short and totally fragmented. As time goes on, however, even when the baby sleeps well, my body wakes me up in no uncertain terms, which will continue until weaning. Nobody can do anything to help me get a full night of sleep, and this time around I can’t even nap during the day since I have a toddler. It seems that sleep is such a necessity, yet parents, especially nursing mothers, are robbed of it relentlessly. I know, I know, the baby needs to be with the mother. I appreciate that, I really do. I just always wonder why, if, as adults, we need continuous sleep so badly (and boy do I ever!), is it taken away from us for literally years of our life? My mom always said mother nature got it wrong in that regard. In the meantime, I sure hope no negative studies of a single cup of coffee ever come to pass.

    • Katherine,
      Richard Hansler addresses this in his e book Great Sleep!Reduced Cancer! They sell a nursery kit on the website The idea is that both the mother and the baby should not be exposed to blue light during the night. Melatonin suppression may even be playing a role in postpartum depression. I was surprised to read that babies do not produce their own melatonin but get it in the breast milk. Think of the implications of that! My babies are all grown up but I have been using the glasses and lightbulbs while training puppy and I believe it has helped me get back to sleep.

    • That is a really good question, Katherine. More lost sleep one of the primary things keeping me from wanting kid #2. DD is 4 now and I’m still recovering from the sleep deprivation; her first year put my body over the edge. If I had to do it all over again I would have quit night nursing much sooner (8 or 9 mos. vs. the 13 or 14 mos. we ended at). DD nursed for 3.5 years total which I’m happy for but the night nursing was bad for both of us in hindsight. It was disruptive to my sleep and hers as well.

      • We ended up cosleeping and my wife could nurse while still asleep or at least with much less disruption to everybody’s sleep. Seems more natural, too.

        • Yes, co-sleeping rocks! I’ve been nursing for more than four years now and I don’t feel sleep deprived at all. My second child was born 16 months ago and is still feeding at night. When there is an exceptional night where I have to get up to comfort him, I can really feel the difference! Nursing while half-asleep is definitely so much easier. For me, Attachment Parenting (co-sleeping and extended breastfeeding) is similar to Paleo in that it looks at our life from an evolutionary point of view. Here’s an interesting article one year ago about how it is to have several chunks of sleep at night inside of an uninterrupted 8-hour sleep:

    • Yes, but not every night. If I notice that my sleep is starting to get funky, I’ll wear them. (Or if I have to use the computer after it gets dark for any significant length of time.)

      • Great article, Chris!

        According to the book, “Great Sleep! Reduced Cancer!: A Scientific Approach to Great Sleep and Reduced Cancer Risk,” by Richard L. Hansler (, there is no need to put the glasses on right after sundown. The best way to use the glasses is to put them on 9 to 10 hours before you usually wake up. And do that consistently — without changing your wake/sleep times by more than a few minutes on any day. If you are getting 8 hours of sleep every night, then you only need to wear the glasses for an hour before bed.

        Furthermore, Hansler says the research on melatonin indicates that a consistent “rhythm” is key (that’s why they call it a “circadian rhythm”!) After all, humans evolved for millions of years with circadian rhythms that were unable to change by more than 5 minutes each day.

        So, the glasses are most effective when they are used in a routine each evening that the body can get used to. So, it really doesn’t make sense to use the glasses after sundown unless you were going to do it every single night. Far easier to just put the glasses on a hour or two before bedtime, and wake up at the same time each day.

        The book is a useful one to read as he explains how the glasses can be used to combat Jet Lag or late night shift work by putting them on at specific intervals to readjust the circadian rhythm. Highly recommend it for anyone interested in this.

      • At CNIB(Institute for the blind) one can get varying levels of amber sunglasses …is it dark amber glasses needed for cutting blue light from computer etc or light or medium shade> they also offer UV and glare shields and “IR” (whatever that is)…how do I chose?

    • Hey, that app is awesome – thanks for the link! Took a little close reading to avoid all the ads, but it installed easily and it couldn’t be much simpler to use. My monitor isn’t easy to dim – this makes it much easier.

    • I installed it, and my very skin sighed with relief.
      But everytime I clicked on something, it flashed, which was even worse than the too-bright screen to begin with. I’m sure there’s a way to fix it, some setting I’ve got set poorly, but I’m not clever enough to figure it out and my googlefu is failing me. Have you heard of anything like that?

      • Sorry JMH – that is a small problem with Pangobright.

        To get techy: I’m guessing what the app does is to create a dark layer “on top” of everything else (at the front) which allows the clicks from the mouse through to other programs. When some other program displays something new, that new things is sent to the “top” (front) and so isn’t hidden by the dark layer. But then Pangobright immediately notices that something is in front of it and gets back “on top”.

        This is by way of saying that I doubt it’s changeable for Pangobright. It would need an entirely different program to achieve the dimming of the screen. I’d love to find one which would avoid that problem!

        For me it’s not a big issue since I tend to use it only last thing as I wind down for the evening.

        @Angel and Jeremy Nelms – glad it’s useful! 🙂

        • Yeah, I figured it’s arguing with some other program for control over the brightness and occasionally loses. I figure if I was a bit more of an educated sys-admin I could figure out what, and how to revoke its permissions, but alas I’m just tech smart enough to be frustrated. *grin* At least I know it’s not just me, then. Thanks though.

      • I also felt the same kind of relief! My screen doesn’t flash if I click on something. It hasn’t failed me, except when it just disappeared from my computer once for some reason. I love it.

    • However, it is not ideal because there still remains high blue in the emitted spectrum. One inexpensive solution is to use a cheap red plastic transparent clipboard– and pop it onto the screen.

    • High fat raw cheese and dates sounds good. f.lux is is AWESOME. I have it on my computer and my phone. It makes such a difference.

  138. Maybe this is a silly question but does light exposure to our skin suppress melatonin as well? Say you’re trying to avoid some type of artificial light at night so you wear an eye mask. Is the eye mask sufficient or would the skin need to be shielded as well?

    • Skin exposure to light can have a mild effect on melatonin production according to a study that was done at Boston University (I think).

      I usually wear a PVC catsuit while watching T.V. at night… it works really well. 😉

    • No, I don’t think artificial light is likely to *significantly* suppress melatonin via its effects on the skin. The orange goggles are sufficient.

    • Robb Wolf mentioned on a podcast that exposure to light has been shown to affect the circadian rhythms of profoundly blind people. The mechanism was something carried on the surface of red blood cells from what I recall. I think it might have been in this episode but sadly the link to the transcript is broken and I’ve not got time to listen to it to check:

      Robb didn’t get into quite how much light it would take, though he advises sleeping in a pitch dark room – and from personal experience, and to my surprise, it works really well.

      I’n still waiting to try the Uvex glasses since Amazon’s courier lost my first order somewhere over the Atlantic! 😉

      • Blind people are still affected by light exposure because there are receptors in the eye that have nothing to do with vision, but are acted on by light to entrain circadian rhythms. I think it has more to do with this than with light hitting the skin, but I could be wrong.

        • Makes sense to me Chris. Though I’m sure there was some mention of someone without retinas still being affected by light. Just thought it was interesting to note but now that the PDF transcript has been fixed – it wasn’t that episode in which Robb mentioned it after all (to save anyone the trouble of looking or listening).

          But getting into the detail here of course. Ultimately sleeping in a pitch black room I find works really well – whatever the mechanism 🙂

          • I highly recommend the book ‘Lights Out! Sugar, Sleep and Survival’. I t really goes into the detail on the subject and I have learned a great deal from it. They actually site a study that indicates that light exposure on the skin does affect melatonin levels, but I am not sure to what extent. Really a great book for anyone interested in the topic of sleep.

      • David, maybe they will send your second pair by drones:) Enjoy your glasses when they finally arrive because I am going to get a pair for my whole family. Glad I came across this article!

    • Hi Kaitlyn, Excellent question! Turns out that only your eyes need to be in the dark in order for your body to produce melatonin. I have been following the research closely by Drs David Blask, George Brainard, Richard Stevens and others… and attended their lectures. Dr David Blask also clarified that you do NOT need to be asleep… just in the dark–pitch black, for a healthy body to produce melatonin. Although, Dr Brainard emphasized that dim red or dim amber night lights positioned close to the flock outlets would minimally affect the circadian, and would be a sensible solution for a late night, safe trip to the bathroom. They both emphasized that the circadian wants bright sunny blue sky days, and dark-dark nights.

    • I’m not so sure about exposing skin to light. Only our eyes have melanopsin. Some studies say you can suppress melatonin by using the skin but another could not repeat the effects. Perhaps some light slipped through the sides of the eye mask in the study. It doesn’t take much light to decrease melatonin levels. Personally, I find that eye masks fall off during sleep.

      A cheap way to black out your room is taping cardboard over your windows and taping black duct tape on the hinge side of your doors.

  139. The three things that I’ve found have worked best for my sleep are wearing amber-colored glasses as soon as the sun sets, a hot Epsom salt bath followed by an ice cold shower rinse and then I top it all off by eating a combo of high fat raw cheese and dates one hour before bedtime.

    Rip Van Winkle in da house!

    • I referenced your name in my post below. Looking up the catsuit gave me quite the belly as The Big Bang Theory is one of my favorite shows and I like the Norman Cousins theory of laughter and illness.

  140. Great article–it should be noted that in order to install f.lux on your iPhone or iPad, you will need to jailbreak the device.

    I’ve had a good experience with the Uvex googles — they’re comfortable enough and you get used to the whole world being orange while you’re wearing them. In fact it gets to be kind of soothing.

    • 1. It is counterproductive if you use f.lux on your phone or computer when there are other lights on – (exception: dim amber or dim red light).
      2. f.lux helps, but does not eliminate the high blue spectrum emitted from computers, phones, or ipads.
      3. solution: use the blue-blocker glasses. I bought a pair for myself & my hubby from I also like their amber night lights.
      4. another solution: avoid the computers at night. go to sleep earlier, and wake up earlier. Use a sleeping mask.
      5. Contact your mayor, alderman and lighting officials. Demand them to STOP the light trespass into your bedroom windows. Speak up at every opportunity. Streetlights that stay on target — the street&sidewalks–(and stay out of your bedroom windows and the night sky) save 1/3 the cost and energy… and are healthier for people and the environment.

      • I have f.lux on my PC and on my jailbroken iPhone. It has made a difference. I monitor my sleep with an iPhone app called Sleep Cycle.

        • ’ve noticed the same thing when I use the Solar Shield brand. I was up until 1 AM doing work the other night and fell asleep nearly immediately when I finally got to bed, thanks to the goggles. Normally I’d be tossing and turning and totally amped up from all the light exposure. (Now if I can just find a way to get all my work done at a more reasonable hour…)

    • I have always enjoyed Amber sunglasses and now reading I understand. My son was a baby in the hospital for 9 days and he was exposed to incubator lights and now he has trouble sleeping. So, I am glad that I came across this article!

      • 8 days is not bad – I work in a hospital and I can tell you that a lot of adults are babies for much longer.

      • Apparently there’s research showing that babies who were kept in the hospital for a while after birth, with all those bright lights, are more likely to develop sleep disorders in later life. I was put into an incubator under blue light to treat jaundice, which will have had a strong impact, and I grew up to have substantial circadian rhythm disorders. I’ve been using darkness therapy for about eight years now, otherwise I end up on a 25 hour day.

    • Um sorry guys but sometimes I can’t fall asleep unless I have the TV on… serious! Am I just lucky? Also I was thinking about every child in the world who can’t get to sleep right now unless you leave the light on… Lol what does this mean? xx

        • I am getting new glasses from my optometrist and decided to order them with BluTech Lenses. Normally I wear blue blocking glasses from or the blue blocker wrap around bifocals in the evening. I am hoping that these lenses will be as effective – they don’t have the yellow tint and look like normal glasses – so it makes them easier for me to wear in the evening when I am out or have company over. And their is no color distortion. Anyone have any idea if they would be as effective? Their website is

    • In your house you could use warm white lights instead of cool whites. Incandescent bulbs are also red end spectrum as well. Do the app and your set to watch TV on your tablet all night long with the lights on.

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