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How Artificial Light Is Wrecking Your Sleep, and What to Do About It

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blue light and sleep, blue light melatonin
Blue light exposure at night can adversely affect a good night's sleep. istock.com/IngaNielsen

“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?#chriskresser #healthylifestyle #artificiallight #bluelight

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)

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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!

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435 Comments

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  1. Wow! Thank you! All the info on this website helped me so much!! I’m going to ace my school project this year!!☺

  2. 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.

  3. 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!

  4. 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 .

  5. 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 Essentials.com. I buy the eye goggles at lowbluelights.com, 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.

  6. 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.

  7. 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.

  8. 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.
      http://www.rosco.com/

      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 essentials.com. 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. http://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side.

      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.

  9. 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: http://justgetflux.com/.
    * For Android phones, you can use blue light filter for eye care: https://play.google.com/store/apps/details?id=jp.ne.hardyinfinity.bluelightfilter.free&hl=en
    * There is preventative eyewear that can be purchased in a yellow tint or clear tint usually from websites such as http://www.taimeopt.com/ or http://www.sleepshield.com/.
    * And finally, I found this article that gives some recommendations on how to protect your vision: http://www.wikihow.com/Protect-Your-Eyes-when-Using-a-Computer

    • 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.”

  10. > 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.

  11. https://justgetflux.com/
    f.lux is a computer program that changes you computers colors to make them warmer to help eliminate the blue light. I use it and it allows me to use my electronics at night without disturbing my sleep

    • > 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: http://ledmuseum.candlepower.us/specx333.htm

      • 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:
          http://publiclab.org/wiki/spectrometer

          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 – CNET.com
          http://www.cnet.com › Computer Accessories › Monitors
          CNET
          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: https://www.google.com/search?q=emission+spectrum+white+LED
          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.

  12. “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: https://www.google.com/search?q=%22warm+white%22+spectrum+spectra+blue

    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
      http://www.lrc.rpi.edu/programs/nlpip/lightinganswers/lightsources/whatisCCT.asp

      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.

  13. 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!!!:)

  14. > ambien
    Check this: http://www.latimes.com/science/la-sci-sn-anxiety-drug-alzheimers-20140909-story.html

    > 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.

  15. 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 lowbluelight.com 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 lowbluelights.com 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.

  16. 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.

  17. You better shop around.

    I’ve long thought the prices at lowbluelights were high, e.g.
    https://www.lowbluelights.com/detail.asp?id=124

    but that sleepzzz.ca 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:
    http://www.aia.org/groups/ek_public/documents/pdf/aiab079025.pdf
    “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)