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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. I’ve read this post several times, and am wondering if you’ve changed any of your recommendations since writing it? Since the posts aren’t dated, although the comments are, it’s difficult to be sure which are your latests opinions. Thanks!

  2. Chris, This is a fantastic article and thankfully i’ve learned over time to whittle my supplement regime down to what you recommend. I’ve always found multivitamins make me extremely anxious, bad tempered and break out in spots, so i’ve learnt the hard way to avoid them. Perhaps it’s the synthetic vitamins that do this?
    Magnesium malate is fantastic and always relieves my head ache and I find cod liver oil really up lifts my mood and generally gives me more energy and sense of well being. I’m trying to avoid acorbic acid as it seems to make my skin flare up so i’m currently waiting for a whole food Acerola Cherry supplement to arrive. i think i need extra Vit C in my diet since i mainly only eat apples and the very occasional orange, although i do have some bell peppers and tomatos on my sandwiches most days of the week (I always worry that because some of my salad is frozen for longer than it probably should be that the Vit C will have degraded?)
    Thanks again for the great article.

  3. Nik….I need help. I have recently been to the dr and my blood work says I am chronically anemic, Vitamin D deficient, Hypothyroid…among others but these are the most significant. I have been taking Synthroid for 9 years constantly increasing, the iron pills NEVER work and now I have, for the past two years, begun swelling all over. Legs mainly. I am so weak and feel like I have run a marathon every second of every day. Why do my doctors not listen to me? I want to treat the cause not the symptom. I am wanting to self medicate. I want to take Iodium 10x 3/day, 85mg vegetarian iron hema-plex, 400mg liquid magnesium and 400IU vitamin E. Do you think this will kill me, because at this point…I’m ready….not suicidal… just tired.

    • Dear Carla. I take Hema Plex for the iron before bed so it doesn’t interfere with Armour thyroid and I take Vit D3 before lunch about 4000 iu. My vitamin D has gone up. Have you tried natural dessicated thyroid. Works better for me but was great on Armour for 13 years but then blood sugar started going up and went through 5 different meds and they made my thyroid medicine race. Now controlling with diet and cinnamon capsules. Take vit C. Chewable calcium. Vit E. Adrenal Complex. DHea 10mg compounded time release for headaches. Magnesium. Multivitamin. Any suggestions for when Armour starts to make me anxious about 3-4 hours after taking. Chewable calcium usually helps. I’m taking 60mg in am and then 30mg at dinner. I had a TT in 2000

  4. The more I understand nutrition and health the more I start to realize that older cultures (Japanese, Chinese, Eastern European) had it right a long time ago. Seaweed seems to be a great choice for balancing the 2:1 ratio of magnesium to calcium. It has a lot of both as well a vitamin C. Plus it’s tasty!

  5. Hi Chris,
    I am on the web reading about vitamin brands. It’s tough to take take it all in and know which one to trust since it is a money-making industry. In the last year I have taken mostly Solgar brand, specifically their B-Complex, Omega 3 EPA & DHA and Omnium (Multi). I am also taking Designs for Health brand Magnesium Glycinate Chelate.

    I recently ran out of my Omnium and a health food store owner recommended I switch brands periodically to get the most benefit (?) so I bought a New Zealand brand called Goodhealth. It is a Women’s Multi & Mineral.

    I live in Mauritius and only get home to the USA once every two years so I try to stock up on good vitamins for the family. I really need help choosing the right brands.

  6. For vitamin D, twenty minutes of exposure to sunlight a day should be enough for most people to reach their daily requirements. However, during the Winter months in the higher latitudes, the amount of sunlight is often not sufficient, hence we dig into our stores from the rest of the year.

  7. Hi Chris, Great article. Interesting about the magnesium. I feel like I have my bases covered but now thinking I should supplement. Funny lately I sometime get numbness in my hands and/or feet. I’m just curious because I’ve always believed you should get supplement s in whole food form. What’s the difference between magnesium like glycinate/ malate and Mega Foods magnesium (they use spinach) Confused on which to take and why. It would be great if you could shed the light. Thanks!

  8. What about building bones? I have read calcium is useless to take but I have a fracture that won’t heal and am a healthy 40 year old athlete with a 1 year old who is still nursing. I have been on paleo for 10 years. Can you suggest something for my brittle bones? Since I was young I have been told I had weak bones after years of riding a bike.

  9. Hi Chris,

    Great series of articles.

    I started taking a magnesium supplement. I took the first tablet in the morning and that night I woke up with a really bad headache and nausea. I didn’t realize it was the magnesium so I took it again the next day and still have this headache and nausea, although its resided a bit now. I also noticed my joints are a bit sore, stiff and cracking a bit. (I’m only 29). I’m fairly sure this is the magnesium? Are you able to comment on this please? Is it possible its the magnesium?

  10. Glad to see I am good with all of these supplements except the K2. You are right, I have never heard of it. Will check it out – thanks for the good information.

  11. Hi Chris, how much of the green pasture cod liver oil should we take per day to meet your vitamin A recommendations? The bottle doesn’t say what the dose of vitamin A is so it’s hard to judge…

  12. Hello everyone,

    I work in a medical environment as a tech. Today one of our nurses was talking with the Nurse Practitioner about a patient who has been having trouble sleeping. They said they’ve tried everything to help including OTC sleep aids. I made a suggestion to the nurse to suggest supplementing with magnesium. I said at least 60% of Americans were deficient in magnesium, the NP quickly replied “No they’re not” in a very condescending manner. I quickly printed off a study that showed the results were 60-80%.

    I’m amazed that so many in the medical community know very little about what our bodies truly need, and diet an nutrition in general.


  13. I started taking Green Pasture’s FCLO/BO combo several months ago at the recommendation of my midwife since I was having headaches and other discomforts. Previously, magnesium had helped with this, but it seemed to be an insufficient amount. Happy to say that the switch away from synthetic vitamins (D, folic acid, etc) to the Royal Blue Ice, an increased dose of magnesium malate has had obvious impacts – no more headaches! And I totally agree with Jack on the cinnamon tingle flavor actually being yummy (can’t stand the chocolate cream though my hubby and 4 y/o seem content with it). It’s also cheaper from Spirit of Health than Amazon with free shipping if you order in bulk. *I have to also credit my midwife for really opening our eyes to organic produce, grass-fed beef, wild seafood, whole-fat dairy, etc. 5 years ago when we first conceived.

    As far as “dosage”, I get that it’s a food so its vitamin content varies, but better guidance for the combo would be helpful. It’s 2/3 FCLO and 1/3 BO. Based on that and the lengthy and confusing recommendations on the Weston Price site, I came up with the following: 3 tsp per day for me (pregnant woman), 2 tsp for hubby, and 1 tsp for my son. Does that sound about right?

    Glad to have discovered your blog and look forward to checking out the Healthy Baby Code!

    • *correction

      that should have said that I switched to “Royal Blue Ice, MegaFoods Baby & Me food-based prenatal for folate and B vitamins, and an increased dose of magnesium malate”.

  14. I take a whole foods multi (new chapter perfect prenatal & nordic naturals dha+d) during pregnancy. Would you advise against that? And if so, what supplements would you reccomend during pregnancy?

  15. Chris, since the brand of supplement can make so much difference, it would be really helpful to know a few brands that you feel are of high quality. Specifically, I’m wondering what brands of Magnesium are high quality?

  16. Taking 5mL Green Pasture FCLO daily – how much of your A, D and K2 needs will be covered? Do you need to supplement beyond that – and if yes how much?