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9 Steps to Perfect Health – #4: Supplement Wisely


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This content is part of an article series.

Check out the series here

In the first three articles in this series, we discussed which foods to eat and which foods to avoid. In this article we’re going to talk about when to supplement and how to do it wisely. We’ve got a lot of material to cover, so you might want to grab a cup of tea and get comfortable!

There are three principles to supplementing wisely:

  • Get nutrients from food whenever possible.
  • Take nutrients in their naturally occurring form whenever possible.
  • Be selective with your supplementation.

Get Nutrients from Food Whenever Possible

Humans are adapted to getting nutrients from whole foods. Most nutrients require enzymes, synergistic co-factors and organic mineral-activators to be properly absorbed. While these are naturally present in foods, they are often not included in synthetic vitamins with isolated nutrients.

In a paper published in the American Journal of Clinical Nutrition called Food Synergy: An Operational Concept For Understanding Nutrition emphasizing the importance of obtaining nutrients from whole foods, the authors concluded:

A person or animal eating a diet consisting solely of purified nutrients in their Dietary Reference Intake amounts, without benefit of the coordination inherent in food, may not thrive and probably would not have optimal health. This review argues for the primacy of food over supplements in meeting nutritional requirements of the population.

They cautioned against the risk of reductionist thinking, which is common in conventional medicine and nutritional supplementation. Instead, they urge us to consider the importance of what they call “food synergy”:

The concept of food synergy is based on the proposition that the interrelations between constituents in foods are significant. This significance is dependent on the balance between constituents within the food, how well the constituents survive digestion, and the extent to which they appear biologically active at the cellular level.

They go on to provide evidence that whole foods are more effective than supplements in meeting nutrient needs:

  • Tomato consumption has a greater effect on human prostate tissue than an equivalent amount of lycopene.
  • Whole pomegranates and broccoli had greater antiproliferative and in vitro chemical effects than did some of their individual constituents.
  • Free radicals were reduced by consumption of brassica vegetables, independent of micronutrient mix.

In short: get nutrients from food, not supplements, whenever you can.

Take Nutrients in Their Naturally Occurring Form Whenever Possible

Synthetic, isolated nutrients don’t always have the same effect on the body. It matters whether the nutrients have been produced by technologic or biological processes, because industrial processing sometimes creates an entirely new compound with different physiological actions.

Trans fat produced in ruminant animals (such as conjugated linoleic acids in dairy products) are beneficial to health, whereas trans fats produced in the processing of industrial seed oils are highly toxic.

Folic acid is another example. The naturally occurring form of folate is not folic acid, a compound not normally found in food or nature, but tetrahydrofolate. While folic acid can be converted into folate, that conversion is poor in humans. It’s also important to note that unlike natural folate, folic acid does not cross the placenta. This is significant because folate is a crucial nutrient for pregnancy, and while folic acid can prevent neural tube defects it doesn’t have the other beneficial effects of folate. What’s more, several studies have shown that folic acid – but not natural folate – increases cancer risk. Unfortunately, folic acid is what’s often used in multivitamins, because it’s significantly cheaper than natural folate.

Be Selective with Your Supplementation.

Multivitamins have become increasingly popular: half of Americans currently take one. But is this a good idea? Most studies show that multivitamins either provide no benefit, or may even cause harm. A study in the Archives of Internal Medicine showed that multivitamins have little to no influence on the risk of common cancers, CVD or total mortality in postmenopausal women. A now infamous meta-analysis in the Journal of American Medical Association, which looked at over 68 trials with 230,000 pooled participants, found that treatment with synthetic beta carotene, vitamin A and vitamin E may increase mortality.

The problem with multivitamins is that they contain too little of beneficial nutrients like magnesium, vitamin D and vitamin K2, and too much of potentially toxic nutrients like folic acid, calcium, iron and vitamin E. This means that multivitamins can actually cause nutrient imbalances that contribute to disease. Another problem is that multivitamin manufacturers often use the cheapest possible ingredients, such as folic acid instead of natural folate – the consequences of which we discussed above.

Which Supplements May Be Necessary?

At this point you might be thinking I’m against supplementation entirely. Not so. No matter how well we eat, some nutrients are difficult to obtain enough of from food alone. There are also circumstances where are need for certain nutrients may increase, such as vitamin C during infections and magnesium with blood sugar imbalances or metabolic problems. In these cases, it makes sense to supplement selectively with beneficial nutrients.

The five nutrients I recommend most people supplement with are:

  • Vitamin A
  • Vitamin D
  • Vitamin K2
  • Magnesium
  • Vitamin C

Vitamin A (Retinol)

Vitamin A is important catalyst for a variety of biochemical processes in the body. It’s required for assimilation of protein, minerals and water-soluble vitamins, and it also acts as antioxidant > protecting body against free-radical damage and diseases like cancer. Vitamin A plays a crucial role in reproduction, promoting full-term pregnancy and proper development of face (eyes, nose, dental arches & lips).

The RDA for vitamin A (2,600 IU) is woefully inadequate, and even then, over 25% of American consume less than half of the recommended amount. Native populations such as the traditional Inuit – which were free of modern, degenerative disease – got much more vitamin A than the average American. The Greenland Inuit of 1953, prior to much contact with the Western world, got about 35,000 IU of vitamin A per day.

Vitamin A (retinol) is only found in significant amounts in organ meats, which explains why many Americans don’t get enough of it. If you follow my recommendations in #2: Nourish Your Body, and you do eat organ meats (especially liver), you’re probably getting enough vitamin A and thus don’t need to supplement. However, if you’re like most Americans and you’ve never eaten liver in your life, you would benefit from supplementing with A.

There’s been a lot of discussion in the media about the toxicity of vitamin A. Some researchers and doctors now recommend avoiding cod liver oil because of this concern. Even Dr. Mercola has jumped on the “vitamin A is toxic” bandwagon. But is this true?

It is true that vitamin A is potentially toxic. Some evidence suggests that excess vitamin A increases the risk of osteoporosis. For example, this study showed both low and high serum A carried double risk of fractures as did optimal levels.

But if we dig deeper we find that excess vitamin A only causes problems against a backdrop of vitamin D deficiency. In his excellent article Vitamin A on Trial: Does Vitamin A Cause Osteoporosis, researcher Chris Masterjohn summarizes evidence demonstrating that vitamin D decreases the toxicity of and increases the dietary requirement for vitamin A. Studies show that supplementing with vitamin D radically increases the toxicity threshold of vitamin A. In a hypothetical 160 lb. person, vitamin D supplementation increases the toxicity threshold of vitamin A to more than 200,000 IU/d. You’d have to eat 22 ounces of beef liver or take 5 TBS of high vitamin CLO each day to get this amount. Not likely!

To meet vitamin A needs (assuming you’re not up for eating organ meats), I recommend taking high vitamin cod liver oil (CLO) to provide a dose of 10-15,000 IU per day. Cod liver oil is really more of a food than a supplement, but since it’s not a normal part of people’s diet we’ll consider it as a supplement.

CLO is an ideal vitamin A source because it also contains vitamin D, which as we just learned, protects against the toxicity of A.

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Vitamin D

Much has been written about the need for and benefits of vitamin D supplementation over the past several years – and with good reason. It’s absolutely critical for health, and up to 50% of Americans are deficient.

We can get vitamin D from two sources: food, and sunshine. Seafood is the only significant source of vitamin D, but you’d still have to eat a lot of it to get enough. 8-9 ounces of herring provides about 2,000 IU of vitamin D, which is a minimum daily requirement for most people to maintain adequate blood levels.

Sunlight converts a precursor called 7-dehydro-cholesterol in our skin to vitamin D3. This D3, along with the D3 we get from food, gets converted by the liver into 25-hyrdroxy-vitamin D (25D), which is what typically gets measured when you have a vitamin D test. The optimal 25D level is somewhere between 35 and 50 ng/mL.

Contrary to what some researchers and doctors have recommended, there’s no evidence that raising blood levels of 25D above 50 ng/mL is beneficial, and there’s some evidence that it may cause harm. Studies show that bone mineral density peaks at 45 ng/mL and then falls again as 25D levels rise above 45. Other studies have shown that the risk of kidney stones and CVD increase with high 25D levels, due to elevated serum calcium levels that accompany excess vitamin D.

However, we also know that vitamin A and vitamin K2 protect against vitamin D toxicity, and vice versa. As I explained in the vitamin A section, fat soluble vitamins exist in a synergistic relationship. It’s possible that the people in the studies above that experienced problems with excess 25D levels were deficient in vitamin A or K2, or both. This is why it’s so important to supplement with all of the fat-soluble vitamins together.

What about sunlight? Well, in summer mid-day sun with pale skin, 30 minutes of direct sunlight will produce 10-20,000 IU of vitamin D. But this is a best case scenario. With darker skin, or different times of year, or buildings that block the sunlight, or increased time spent indoors, we won’t be producing that much. It’s also true that aging, overweight and inflammation reduce our conversion of sunlight to vitamin D. This is why sunlight alone isn’t normally a sufficient source of vitamin D.

With this in mind, most people should supplement with D. The amount needed to maintain blood levels of 35-50 ng/mL varies depending on some of the factors I’ve listed above, but in my clinical experience it’s usually somewhere between 2,000 – 5,000 IU.

With vitamin D, it’s important to test your levels, begin supplementation, and then re-test a few months later to determine the correct maintenance dose.

As with vitamin A, the best source of vitamin D is high-vitamin cod liver oil. It contains not only vitamins A & D, but also natural vitamin E and other quinones.

Vitamin K2

Vitamin K2 may be the most important vitamin most people have never heard of. It’s needed to activate proteins and it also regulates calcium metabolism (keeping it in the bones and teeth where it belongs, and out of the soft tissue where it doesn’t belong). Elevated blood calcium significantly increases the risk of cardiovascular disease (CVD), which explains why vitamin K2 has been shown to prevent atherosclerosis and heart attacks. It also strengthens bones.

Unfortunately, many (if not most) of Americans are deficient in vitamin K2. It’s important to point out that vitamin K2 is not the same as vitamin K1, which is found in green, leafy vegetables like kale and collards. Some K1 is converted into K2 in our bodies, but that conversion is inefficient in humans. It is efficient, however, in ruminant animals – which is why grass-fed dairy is the most convenient source of vitamin K2 in the diet. This is only true in animals raised on pasture, because it is eating the K1-rich grass that allows them to convert it into K2.

Most people should aim for at least 100 mcg/d from a combination of food and supplements. If you eat a large amount of cheese from grass-fed cows and pastured egg yolks, you may be able to get this amount from food alone. 100 g of hard cheese contains 67 mcg, and 6 pastured egg yolks contain about 32 mcg. Otherwise, supplementation is probably beneficial. I recommend a dosage of 1 mg/d in the MK-4 form, which is the form of vitamin K2 found in pastured dairy and the one shown to have the most benefit in clinical studies. There is another form, MK-7, that is found in fermented foods like natto, but it has not demonstrated the same properties as MK-4 in clinical studies.


There are few compounds in the body more important to overall health than magnesium.

Over 300 enzymes need it, including every enzyme associated with ATP, and enzymes required to synthesize DNA, RNA and proteins. Magnesium also plays an important role in bone and cell membranes, as it helps to transport ions across the membrane surface.

Studies show that most Americans are deficient in magnesium. The median intake across all racial groups is far below the RDA, which is 420 mg/d for men and 320-400 mg/d for women. Although half of Americans take a multivitamin daily, most don’t contain enough magnesium to prevent nutrient deficiencies.

Magnesium is also difficult to obtain from food. Nuts and seeds are the highest source, but it’s difficult to eat enough of them to meet magnesium needs without getting too much polyunsaturated fat. Another issue is that magnesium levels in food have dropped as modern soils have become increasingly depleted. What this means is that if you’re not supplementing with magnesium, you’re probably not getting enough.

And magnesium deficiency is no small thing. It has serious – even fatal – consequences. It produces symptoms like muscle cramps, heart arrhythmias, tremor, headaches & acid reflux, and it’s associated with CVD, hypertension, metabolic syndrome, diabetes, migraines, PMS, asthma, hypothyroidism. In fact, it’s hard to find a modern disease magnesium deficiency isn’t associated with.

Because of this, I think everyone should supplement with magnesium. Intake of 400 – 800 mg/d from a combination of food and supplements is an optimal range to shoot for. Since most people get less than 250 mg/d from food, a dose of 400 – 600 mg/d in supplement form is ideal. I recommend using chelated forms of magnesium like glycinate and malate, because they’re better absorbed and tend to have fewer side effects.

Vitamin C

Vitamin C is needed for building the structural components of the body, and for maintaining levels of glutathione, the master antioxidant in the body. But vitamin C deficiency is also common: studies suggest that 34% of men and 27% of women don’t get enough. This is especially true for the elderly and those struggling with chronic illness.

400 mg/d is the saturation range in healthy people, and that number is probably higher in the elderly and the sick. As with the other micronutrients in this article, it’s difficult to obtain adequate levels of vitamin C from the diet. Acerola cherries are the highest food source, with 1677 mg per 100g. A cup of cooked red peppers has 235 mg, which is one of the highest dietary sources.

I’m somewhat less certain about the need to supplement with vitamin C, but in general I recommend approximately 500 mg to 1 g of vitamin C each day. If you’re dealing with a chronic health challenge, or fighting an infection, you can take several grams a day with no toxic effects. It’s best to space the doses out to avoid diarrhea, however.

Other Contenders

In addition to the fat-soluble vitamins A, D & K2, and magnesium and vitamin C, some may want to consider supplementing with selenium and iodine. Selenium plays important role in thyroid function, which affects every aspect of physiology. The recommended dose is approximately 200 mcg/d.

Selenium is plentiful in organ meats, ocean fish, and in brazil nuts. One brazil nut contains 100 mcg of selenium, but it also contains a whopping 1 g of omega-6 linoleic acid, which as you know from previous articles in the series, we want to limit significantly. This is why I don’t recommend brazil nuts as a source of selenium. Ocean fish are also good sources of selenium. 100 g of cod contains about 150 mcg.

Iodine also plays a crucial role in thyroid function, and it prevents brain damage and strengthens the immune system. The amount iodine needed for thyroid function is incredibly small: we need about a teaspoon of iodine over a lifetime to avoid deficiency.

I’m not convinced humans need to supplement with iodine above what can be obtained from seafood, but some research does suggest that increased intake of iodine is beneficial. This is especially true if you’re fighting a chronic infection or dealing with a hypothyroidism caused by iodine deficiency.

But be careful: iodine can trigger and flare autoimmune diseases, especially Hashimoto’s and Graves'(autoimmune thyroid disease). In the U.S., 9 out of 10 women with hypothyroidism actually have Hashimoto’s, so the typical advice to supplement with iodine if you are hypothyroid is dangerous. I’ve written extensively about this in my special report on thyroid disease.

For those without autoimmune disease, a dose of 12.5 mg – 50 mg per day may be beneficial, but it’s best to work up slowly over time, beginning at a much lower dose.

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Join the conversation

  1. Chris,

    I had an interesting experience with Iodized table salt. For about 2 weeks now, I have dropped regular salt for Pink Himalayan salt. It occurred to me the other night that I might be needing iodine (I’m not well versed on other good sources or symptoms of Iodine deficiency). Anyhow, I made some eggs and added iodized salt instead of Himal Pink, and within 2 hours, I was dead tired. I woke up the next morning and felt like I had no energy/lethargic, and this feeling lasted for nearly half the day!

    As far as I can think, that was the only thing I had done/eaten differently. What are your thoughts? I may try it again tonight, to try and narrow it down, but I hadn’t felt that de-energized in a long time.

  2. hi chris ,
    I read from above that you change your mind about kelp , Is that change of your opinion ??

  3. Hi Chris,

    Thank you for all of the excellent info! I’m wondering about magnesium supplementation and tiredness. Whenever I take only 100mg of Mg glycinate at night, I feel simply wiped-out the next day and heavy-headed. Any thoughts on this? I rarely take the supplement because of this, but I know it’s important.

    Thank you!

  4. Chris,

    Saw this article, http://www.thehealthyhomeeconomist.com/which-vitamin-k2-supplement-is-best-mk-4-or-mk-7/ from Sarah Pope of the Healthy Home Economist blog. She references a book, Vitamin K2 and the Calcium Paradox by Dr. Kate Rheaume-Bleue BSc, ND (http://www.amazon.com/gp/product/1118065727?ie=UTF8&tag=theheahomec0a-20&linkCode=xm2&camp=1789&creativeASIN=1118065727) claiming the Mk-7 variant of K2 is superior because the MK-4 variant is synthetic and derived from the tobacco plant and also that the MK-4 variant stays active in the body for a shorter time.

    Do you have an opinion on this?


  5. Hi Chris,

    Wow, thank you for sharing this great information and responding to so many comments! This article has motivated me to try a CLO/BO combination as a supplement since I live in a climate with limited sun.

    I have to admit that I’m feeling confused about magnesium. You mentioned that it is rare in foods and a quick Google search confirms that most foods containing significant amounts of magnesium either wouldn’t have been part of a natural diet (e.g. grains) or would have been rare and difficult to obtain (e.g. molasses, nuts, etc).

    What would our ancestors have eaten that provided magnesium? My goal is to get all of my nutrition from food or food derived sources. I eat sardines and eggs daily and liver weekly since I know these are all powerful foods when it comes to nutrients. Do you have any recommendations for food sources for magnesium besides nuts?

    Thank you,


  6. Thank you for a very informative post and website. I note that your basic recommendations do not include B complex, which is frequently recommended for various conditions including fatigue and mood disorders. As you know, B complex pills contain far far more of certain vitamins than one could ever get in the diet, perhaps because the manufacturers know most of them will not be absorbed. If you already commented on B complex I apologize for missing it, but would be interested in your thoughts. Personally, I take an “active” B complex, and in the past have taken a “whole food” B complex.

  7. Hi,
    I really love you work. I spent a long time reading and digging around and never really geot to the bottom of things and ultimately need to confide in someone who spends and devotes their life to research. I now confide in your podcast, and other stuff that you do – thank you.
    I’ve been paleo for 18 months and influence my children as much as possible, but without 100% success. I’m always working on other ideas to generate more success, but as with many things, I would like a support net in place. I would like to know if this article would be written any different if you we’re targeting it to the next generation – our children. What supplements would it be narrowed down to, amounts and which brands (if I’m using you as a one stop shop, as lots of people do, we would prefer to know what to take, why we take it, when we take it and which brand – we know your hearts in the right place and your not peddling brands for kudos.
    My boy is 9 and my girl is 12. Both extremely sporty and strength train for sport as well. There always on the go and i’m like a walking fridge most of the time, keeping them topped up with carbs and protein before during and after. However, every time I think I’m getting it right I read something suggesting otherwise. What supplements should they be taking to keep things on track. Kids often don’t eat all the right things or at the most appropriate times. Nutrition for basic life seem to differ considerably to sports nutrition and sports nutrition seems more divided on opinion. Help is required from one father to another!

  8. At Whole Foods you can find a product called “Strauss Free Raised premium calf liver”. It’s usually in the freezer right near the meats section.

    It’s perfect to get your Vitamin A (not to mention just about every mineral), and it doesn’t taste anywhere near as gamey as beef liver. In fact, it’s *almost* delicious, especially when cooked in some Kerry Gold. 🙂

  9. Hi Chris, i was wondering, what supplement would you suggest for a pregnant women?and if there is a particular brand you would recommend. thank you very much

    • That’s a hard question to answer. There are many considerations. Fermented cod liver oil is a great choice for most pregnant women, as is extra folate. Check out my Healthy Baby Code program for more detail on this subject. http://healthybabycode.com

  10. Dear Chris,
    I am more interested to know about the folic acid supplementation vs folate dietary intake.

    The following studies both state that folate absorption from supplements were better than dietary sources:

    Geraldine J Cuskelly, Helene McNulty, and John M Scott, Effect of Increasing Dietary Folate on Red-cell Folate: Implications for Prevention of Neural Tube Defects, Lancet 34 7(9002): 65 7-659 (9 Mar 1996) [Correspondence: Helene McNulty, Phd, School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK]


    What are your thoughts on this?

  11. I’ve tried Green Pastures CLO + Butter Oil blend but I notice it lists the 2 pill dose as providing 1800 IU of Vitamin A. Here you say CLO is a good source for Vit A and people should be looking to take in over 10,000 IU a day. That’s a hell of a lot of pills – over ten a day. Especially for an expensive supplement.

    How much CLO do you take?

    By the way, a favorite snack for my Polish family when I was growing up was tinned cod liver laid out over cream cheese on bread. I know the bread is anathema but just saying cod liver out of the tin is a real treat.

  12. White Flower Oil (http://embrocation.50webs.com) was introduced to me by my mother. During one of my headaches, she gave me this tiny bottle of oil and told me to massage it on my temples and forehead. Amazingly, it worked! Somehow the oil penetrates into the affected area and relieves the pain.

  13. Hi
    is 100mcg/d of MK-4 going to help? I’m supplementing with 10000 IU-vitamin A and 2400 IU-Vitamin D
    Just because K2 supplements are more expensive.

  14. Chris,

    I’m really enjoying this series and I really appreciate you sharing this information. My question is about Vitamin D. I’ve always heard that 30 minutes in the sunlight produces so much Vitamin D but I’ve always wondered how much skin exposure is normally tested. In other words, you mentioned with pale skin, 30 minutes of direct sunlight will produce 10-20,000 IU of vitamin D. Is this measured with a certain amount of skin exposed like short sleeve shirt, face exposed or shirt off etc.?

  15. Wow. I just found and read your articles from mid 2010 on Iodine and Hypothyroidism. I didn’t know you had done so much work on that topic. I hope I am not making a mistake by beginning iodine supplemenation with the kelp tablets. I have seen on multiple sites that iodine supplementation is probably a good idea for most people, and that the vast majority of folks are deficient from their diet. So I finally took the leap. From what I understand, it takes quite a while to see any differences if I am even going to at all, like 6 months or something.