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Nutrition for Healthy Skin: Silica, Niacin, Vitamin K2, and Probiotics


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Note: The Prescript-Assist supplements discussed in this article are no longer available. Please click here to learn more about a substitute, the Daily Synbiotic from Seed.

It’s time to close out my series on nutrition and skin health. I believe that a nutrient-dense, whole foods diet, with particular attention paid to certain vitamins, minerals, and other compounds, is a powerful tool in the treatment of skin disease. It’s unfortunate that many mainstream doctors and dermatologists typically deny any connection between diet and skin health, and many patients miss the opportunity to make major improvements in their skin simply by changing what they eat. I hope that this series will give you the evidence you need to make the switch to a skin-supporting diet.

It’s unfortunate that many mainstream dermatologists deny any connection between diet and skin health. Tweet This

In this final article, I will discuss the benefits of four nutrients that can play an important role in improving the look and feel of one’s skin: silica, niacin, vitamin K2, and probiotics. (Yes, probiotics are not a nutrient, but they may be one of the most important parts of a healthy skin diet!)

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While silica may not be considered an essential nutrient by current standards, it is likely that this trace mineral plays a functional role in human health. (1) In animals, a silica deficient diet has been shown to produce poorly formed connective tissue, including collagen. In fact, silica has been shown to contribute to certain enzyme activities that are necessary for normal collagen formation. Silica is essential for maintaining the health of connective tissues due to its interaction with the formation of glycosaminoglycans (GAGs), which are structural building blocks of these types of tissue. One well-known GAG important for skin health is hyaluronic acid, which has been shown to promote skin cell proliferation and increase the presence of retinoic acid, improving the skin’s hydration. (2)

Therefore, a deficiency in silica could result in reduced skin elasticity and wound healing due to its role in collagen and GAG formation. As we know, proper collagen formation is essential for maintaining tight, wrinkle-free skin, so silica can also be beneficial for slowing down the signs of skin aging.

It’s best to get silica from natural sources, and food sources of silica include leeks, green beans, garbanzo beans, strawberries, cucumber, mango, celery, asparagus and rhubarb. (3)

Silica can also be found in certain types of water, such as Fiji brand water, which contains more than four times the levels found in other bottled waters due to the leaching of water-soluble silica from volcanic rock. (4) In fact, beverages contribute to more than half of the total dietary intake of silica, and the silica content of water depends entirely on its geological source. Silica can also be found in trace mineral supplements, such as ConcenTrace Trace Mineral Drops, which can be added to plain drinking water.


Niacin, also known as vitamin B3, plays a vital role in cell metabolism as a coenzyme in energy producing reactions involving the breakdown of carbohydrates, fats, and proteins, as well as anabolic reactions such as fatty acid and cholesterol synthesis. (4) The deficiency of niacin is rare these days, but was fairly common historically due to the reliance on niacin-poor food staples, such as corn and and other cereal grains, in low-income communities. (5) Pellagra, the disease of late stage niacin deficiency, causes a variety of skin symptoms such as dermatitis and a dark, scaly rash. In fact, the word “pellagra” comes from the Italian phrase for rough or raw skin. (6) The skin symptoms are often the first to appear, and may be exacerbated by even a slight deficiency in niacin over a long period of time.

While a low intake of niacin is unlikely, there are some diseases that may cause inadequate niacin absorption from the diet. An example of this is in celiac disease, where absorption is impaired by the swelling and thickening of the intestinal lining that occurs in celiac disease. (7) Other inflammatory gut conditions such as IBS or Crohn’s disease can also lead to a reduction in niacin absorption, and could conceivably lead to the skin-related symptoms of pellagra such as dermatitis and scaling.

Good whole-foods sources of niacin include meat, poultry, red fishes such as tuna and salmon, and seeds. Milk, green leafy vegetables, coffee, and tea also provide some niacin to the diet. Your liver can also convert tryptophan from high-protein foods like meats and milk into niacin. (8)

In the case of true deficiency, supplementation may be necessary, but for most healthy people, a varied diet with adequate meat consumption should be enough to meet one’s nutritional needs.

If choosing to supplement, be sure to consult with a licensed medical professional, as too much nicotinic acid can be harmful.

Vitamin K2

I’ve written before about the incredible health benefits of a diet rich in vitamin K2. Vitamin K2′s role in the body includes protecting us from heart disease, forming strong bones, promoting brain function, supporting growth and development and helping to prevent cancer – to name a few. It performs these functions by helping to deposit calcium in appropriate locations, such as in the bones and teeth, and prevent it from depositing in locations where it does not belong, such as the soft tissues. One of the health benefits of vitamin K2 not often discussed is its role in ensuring healthy skin, and this vitamin is likely beneficial for preventing wrinkling and premature aging.

Adequate dietary vitamin K2 prevents calcification of our skin’s elastin, the protein that gives skin the ability to spring back, smoothing out lines and wrinkles. (9) This is because K2 is necessary for activation of matrix proteins that inhibit calcium from being deposited in elastin fibers and keeping these fibers from hardening and causing wrinkles. In fact, recent research suggests that people who cannot metabolize vitamin K end up with severe premature skin wrinkling. (10) Vitamin K2 is also necessary for the proper functioning of vitamin A- and D- dependent proteins. As I discussed in the first article in this series, vitamin A is essential for proper skin cell proliferation, and cannot work properly if vitamin K2 is not available. Therefore, vitamin K2 is important in the treatment of acne, keratosis pillaris, and other skin symptoms of vitamin A deficiency.

It’s important to get adequate amounts of dietary vitamin K2, particularly if trying to heal the skin or prevent wrinkles. Great sources of vitamin K2 include butter and other high fat dairy products from grass-fed cows, egg yolks, liver, and natto. Fermented foods such as sauerkraut and cheese are also quite high in vitamin K2 due to the production of this vitamin by bacteria. It is important to note that commercial butter and other dairy products are not significantly high sources of vitamin K2, as most dairy cattle in our country are fed grains rather than grass. It is the grazing on vitamin K1-rich grasses that leads to high levels of vitamin K2 in the dairy products of animals, so be sure to look for grass-fed dairy products when trying to increase your intake of vitamin K2. (11)

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Probiotics are one of the most fascinating areas of modern nutrition research, and a topic I am passionate about. I will be discussing what is known as the “gut-brain-skin” axis during my presentation upcoming at the Weston A. Price Foundation Wise Traditions Conference in November, and have been researching the connection between gut flora and skin conditions for months. While there is a great deal of information on the skin-gut axis, I’ll give a quick summary of the information in this article – the rest you’ll have to see in my presentation in a few months!

The skin-gut axis has been studied since the 1930s, and yet we’re only just beginning to understand the role that probiotics may play in skin health. The ability of the gut microbiota and oral probiotics to influence systemic inflammation, oxidative stress, glycemic control, and tissue lipid content, may have important implications in skin conditions such as acne, rosacea, atopic dermatitis, and psoriasis. (12) Recent studies have shown that orally consumed pre and probiotics can reduce systemic markers of inflammation and oxidative stress, which may help reduce inflammatory acne and other skin conditions. (1314, 15) There is also a connection between small intestine bacterial overgrowth (SIBO) and the incidence of acne, suggesting that reestablishing the proper balance of gut microflora is an important factor in treating acne.

There are far more beneficial effects of probiotic bacteria for skin health than I will be able to mention in this article; I will cover the topic much more in-depth at the conference in November.

However, I believe the evidence strongly supports the role of probiotics in treating a variety of skin conditions, and recommend that anyone suffering from skin trouble be especially diligent about including fermented foods such as sauerkraut, kimchi, yogurt, and kefir in your regular diet.

Probiotic supplements can also be helpful—but be careful, because not all probiotics will be beneficial for skin conditions. As I’ve mentioned, many people with skin conditions also have SIBO. SIBO often involves an overgrowth of microorganisms that produce a substance called D-lactic acid. Unfortunately, many commercial probiotics contain strains (like Lactobacillus acidophilus) that also produce D-lactic acid. That makes most commercial probiotics a poor choice for people with SIBO.

Soil-based organisms do not produce significant amounts of D-lactic acid, and are a better choice for this reason. In my clinic, I have great success with a product called Prescript Assist when treating skin conditions. Other popular choices include Gut Pro from Organic 3 and D-Lactate Free Powder from Custom Probiotics. I used these in the past, but have much better success with Prescript Assist so I now use that exclusively.

Well that’s the end of the “Nutrition for Skin Health” series! As a quick recap, the top whole-foods nutrients I recommend as part of any skin-healing diet are:

  • Vitamin A
  • Zinc
  • Vitamin C
  • Omega-3 Fatty Acids
  • Biotin
  • Sulfur
  • Vitamin E
  • Pantothenic Acid (vitamin B5)
  • Selenium
  • Silica
  • Niacin
  • Vitamin K2
  • Probiotics

I hope this information has been helpful to you, and I would love to hear any success stories from readers who have treated their skin conditions using nutritional changes!

Other articles in this series:

Nutrition for Healthy Skin: Vitamin A, Zinc, and Vitamin C
Nutrition for Healthy Skin: Omega-3 Fatty Acids, Biotin, and Sulfur
Nutrition for Healthy Skin: Vitamin E, Pantothenic Acid, and Selenium

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  1. Red palm oil contains tocopherol and tocotrienols which is why I was afraid of overdosing on its vitamin A-

  2. Also, is it safe to eat liver and extra virgin red palm oil while taking cod liver oil? red palm oil is very rich in vitamin A and I don’t want to overdose.

    • I doubt there would be a problem taking both (I do).
      keep in mind, palm oil doesn’t actually contain any vitamin A, (which is only from animal sources) it just has lots of carotene, which your body can convert to Vit A. But, your body only does the conversion if you are vit a deficient, so it’s hard to overdose on carotene – though, like anything, taken to extremes it could be a problem.

      Besides, red palm oil has so many other goodies in it that it is worth taking in its own right – it is the most nutrient dense plant oil there is.

      Just be careful not to spill/splatter it – it stains everything an orange colour!

      • quote “your body only does the conversion (carotene to vitamin A) if you are vit a deficient”.
        Not sure if this is wholly true, from what i have read, good Thyroid function is required to convert carotene to vitamin A. So this may be an issue in people who are on the hypothyroid end of the scale.
        I have also read that Vitamin A is required for good thyroid function, so this could be a bit of a catch 22 for people relying on carotene for Vitamin A.
        (Sounds like it may be better to get Vitamin A from animal sources if your thyroid function is low or compromised?)

        for more info, google something like ‘carotene conversion thyroid’ also ‘carotoderma thyroid’

        • I think what was meant is, you won’t get extra Vit A from carotenoids, not that you’ll always get enough. Conversion of carotene to retinol requires tocopherol for stabilization, otherwise you get asymmetrical split forming apocarotenoids that have anti-retinol activity.

          • yes, that is what was meant.

            I see now that nutritional labels, and many writers, especially vegan ones, regard carotene as vitamin A.

            Given the various co-factors required for the conversion, and the presence of fat even for the absorption of carotene (which many vegans avoid), I think this is misleading at best.

            I have read somewhere that that carotene is not very bioavailable in raw veg, it needs to be cooked to get it all out. So the raw vegans eating carrots and the like without any oily accompaniments are probably getting vitamin a deficient (amongst other things) .

  3. Hi Chris, I purchased cod liver oil from Green Pastures but I meant to get the cod liver oil/butter blend. Right now, to maximize absorption, I’m eating a spoonful of grass fed butter alongside my cod liver oil. The ratios are probably off, but do you reckon this is still effective? My goal is to clear my skin for good. Thanks much

  4. Hi Chris, I have problems tolerating dairy products – I think it’s the casein that’s the problem – so would it be better to supplement with K2 in the MK-4 form? Things like sauerkraut and fermented foods don’t agree with me either..

  5. I have changed my diet quite a bit the past few months. Due to my husbands intolerance to gluten I was eating less of it, but did eat it occasionally. But when I became pregnant I started avoiding it as much as possible. And after the birth of our daughter found out she cant have any type of dairy product, now I avoid all forms of dairy. all of that being said: I have found my skin staying so much more clear and less oily! Also I feel better with my whole digestive system as well. Nutrition is linked to our health in every single aspect! I find it so sad so many don’t see the connection until they encounter a serious health issue.
    Shanna M.

    • It’s in Santa Clara. It’s called the Wise Traditions Conference, and it’s put on by the Weston A. Price Foundation.

  6. I started doing GAPS in february, after listening to your podcast about the gut-brain-skin axis. I have celiac disease so I figured my acne might have something to do with leaky gut and dysbiosis, and voila, my face looks terrific now. Things were improving very quickly after I started taking probiotics. Just wanted to say thank you, Chris.

    • Hi Bodil,
      It looks like you are the only one who can help me; I researched online but did not find anything worthy other than your above statement which says “I started doing GAPS in february, after listening to your podcast about the gut-brain-skin axis. I have celiac disease so I figured my acne might have something to do with leaky gut and dysbiosis, and voila, my face looks terrific now. Things were improving very quickly after I started taking probiotics. Just wanted to say thank you, Chris.”.
      Could you please tell me what GAPS is? I tried 3 different probiotics: Started with Kefir, then a potent tablet probiotic, then a specially-designed capsul probiotic that has the potential to travel far in the guts but all caused my acne/rosacae get 10 times worse permanently (after 2 months, no improvement), moreover, except for Kefir, the other 2 probiotics made me extremely bloated as well. I would be greatful if you can share your experience.

      • GAPs is “Gut And Psychology Syndrome” and it’s a diet. I would wonder about whether or not you have healed your gut if you are reacting still to the probiotic. I have gluten intolerance, leaky gut and I don’t tolerate probiotics well. The GAPs diet is a good choice to try and heal the gut as are Specific Carbohydrate Diet and Paleo. I like Paleo (plus potatoes aka the Perfect Health Diet) the best. You may have SIBO- Small Intestinal Bacterial Overgrowth, which also causes bloating. There is a test for that called the hydrogen breath test.

  7. Very curious to hear your thoughts on my situation. I have been diagnosed with SIBO and rosacea. After a round of antibiotics my skin improved. Have since been following SCD but everytime I take probiotics or eat yogurt my skin breaks out again! It is a bit frustrating as I read so much about them being helpful and I’m not sure why they backfire for me.

    • My guess is you still have some lingering SIBO. Lactic-acid forming probiotics can make SIBO worse. I would either avoid lactic-acid ferments or probiotics until you get the SIBO under control, or try a D-lactate free probiotic such as the one from Customprobiotics.com

  8. A linoleic acid deficiency &/or an arachidonic acid deficiency could result in bad skin (dry, scaly, itching skin, hair loss, dandruff, inflammation).
    (& the arachidonic acid deficiency could be a result of a linoleic acid deficiency, part of the omega-6 metabolic pathway, if you are not getting enough AA or GLA in you diet).
    Probably rare, but worth a mention, both of these are omega-6 fatty acids.

  9. L’Oreal have developed a probiotic extract that reduces irritation in sensitive skin. There are two interesting features here – a probiotic need not be alive to confer an immune-modulating benefit, and, the gut is far from being the only area responsive to probiotics.
    The killed probiotic effect I characterize as an immune reboot. Redundant antibodies are retired, fresh NK cells generated, so there is a relaxation of backwards-looking vigilance and a simultaneous creation of fresh alertness. Like replacing the worn-out staff of an army with freshly trained men, and replacing dated equipment with the latest models. This tends to boost immunity while reducing autoimmunity.
    Live probiotics add to this effect the production of many beneficial chemicals, including ATP, neurotransmitters including GABA, butyrate, endorphins, vitamins, and antimicrobial peptides.

  10. Chris,

    You’ve suggested 9 supplements to improve the skin, yet no dosage levels. Also, are there some of these vitamins/supplements that are bundled together? I’m a firm believer in supplementing my diet in addition to trying my darndest to get what I need from food. It’s not always easy to get everything you need from food alone. My cravings are under control when I keep up with supplements and I’ve noticed a marked difference in what I HAVE to have (citrus always hits me hard) vs what just feels like “meh”.

    Might I also recommend a night cream for the face (and neck): it’s by Nature’s Gate Organics and the one I use is called Oh What a Night Walnut Therapy (you can find it on Amazon). My skin usually has bumpy dry patches that any amount of scrubbing could not erase for more than a few hours. I’ve been using this cream for 4 days and I wake up with dewy skin every single morning that lasts throughout the day. I wish I sold this product! It has changed the way I take care of my facial skin…now when I figure out the supplementing part WITH this night cream: look out world!!

    Thank you as always for your informative articles,

  11. Chris,

    Great series. As I noted in the second part of my blog series on small intestinal bacterial overgrowth (SIBO) at syontix.com, it is not at all unusual to see skin issues associated with SIBO due to malabsorption. That was one of my indications something was not right with me even though I was eating a very nutrient-dense diet with no processed foods whatsoever.

    Besides horribly dry skin, I also either had rosacea or dermatitis as one dermatologist would say one thing and another would say something else. Regardless, I would be sent out the door with a cream (it had a skull and crossbones warning on it for increased cancer risk) that barely worked. At this time I also had very bad jock itch that another prescription cream could barely keep under control. Asking any of the dermatologists if this could be diet related brought either blank stares or protestations that there is NO proof for a diet connection…..sigh.

    However, once my SIBO was taken care off, all this disappeared and my skin has never looked healthier!

    • Hi Ray,

      Yes, SIBO and other gut issues are often at the root of skin problems. This series was focused on nutrients for skin health; in a future series, perhaps I’ll cover the gut-skin connection. My talk at the Wise Traditions conference in November will be on this subject (more specifically, on the gut-brain-skin axis).

    • Hi. I also have SIBO and the skin issues you are referring to that you had. What can I do? Can this really all be taken care of? My GI system and skin are horrible. Anything you can help with I appreciate, please!

      I feel worse taking probiotics yet I’m told to take them? Also, if I eat sourkraut from whole foods, I have diarrhea, but I never knew of D-lactic.

      Thanks, Anthony

  12. Taking Green Pasture’s Fermented Cod Liver Oil and Butter Oil blend does it matter if it is the capsule form?

    • I asked Chris this very question previously and he said there are no differences in health benefits, just the cost.

  13. Regarding probiotics, I have been thinking of consuming water kefir regularly. I noticed it is very sweet, due to the sugar content. It is very sweet even after several days of fermentation. Do you think the benefit of the probiotic outweighs the sugar?

    • That’s odd. When I ferment mine for a week it’s pretty sour. But yes, I think the sugar content is fairly minimal and the probiotic content is definitely beneficial.

      • Is not the maximum fermentation time for water kefir 48 hours? After this time the bacteria has consumed all the glucose and they’ll starve if left in that solution any longer. That was what I’ve been told about water kefir from the from the ferment community from the get go.

    • I like Therbiotic Complete from Klaire Labs. Jarro-Dophilus EPS is a good shelf-stable option.

      • I noticed there are no specifications on how many cfu’s per individual bacterium there are for Jarrow Eps. That still ok?

    • Hi Chris

      First off I want to say thank you for your insightful information and I’m getting ready to implement these recommendations into my life.

      I have been battling with acne for years and just have two questions. I’m eager to try a probiotic. You mentioned Lactobacillus can be a problem with people who have SIBO, yet it’s mentioned here and elsewhere that Lactobacillus is effective against acne. I’m confused should people with acne take probiotics with Lactobacillus?

      Also based on your recommendation I’m going to order Green Pasture Fermented Cod liver oil + butter oil to get the vit K2? My question is do you think the butter oil could contain anything like IGF-1 that would cause acne? I hope you can answer my questions.

      Thank you and your feedback is appreciated.