The Big Vitamin D Study Was Wrong

Vitamin D3 Really Does Work

That big vitamin D study funded by the government concluded that Vitamin D supplements don’t work. Here are all the things they got wrong.

A Very Questionable Vitamin D Study

Conducting scientific studies like the following would probably be silly:

  • A study to test the efficacy of a new birth control pill using octogenarians as test subjects.
  • A study to test a new erection pill using the Unsullied, who’ve had both pillar and stones removed.
  • A study on the ability of fleece-lined thermal underwear to keep women who live in the Sonoran Desert warm.
  • A study to see if dogs really do love bacon, only using chipmunks instead of actual dogs.

If you used just a tiny bit of brain power, you could probably guess that any results obtained from such studies might not make much sense or have much applicability to anything.

Well, that’s pretty much how I feel about the big vitamin D study (VITAL) that just came out – the one that said that you don’t need to take vitamin D supplements (or even test levels of the vitamin) because they don’t help to protect bones from fractures or do much of anything else either.

Their study, titled “Supplemental Vitamin D and Incident Fractures in Midlife and Older Adults,” neglected to consider any number of extenuating factors that likely affected the results.

So, What Exactly Did The Study Say?


The study, published in the New England Journal of Medicine, involved roughly 26,000 generally healthy people in their 50’s or older. The aim of the randomized, controlled study (funded by the U.S. Government), known as VITAL, was to compare bone fractures in people who took a “high” dose of vitamin D3 (2,000 international units), n-3 fatty acids (1 gram per day), or a combination of both, for five years.

Taking vitamin D (or omega-3 fatty acids) didn’t appear to reduce the risk of broken hips or other bones. Neither did it seem to help prevent any major diseases. It also didn’t help prevent falls, reduce atrial fibrillation, change body comp, improve cognitive functioning, improve stroke outcomes, reduce frequency or severity of migraines, prevent macular degeneration, or reduce knee pain.

Their message, in an accompanying editorial, to the people who regularly supplement with vitamin D? Don’t bother.


Now I’ve not spent a lot of time studying those aforementioned aspects of vitamin D supplementation. Instead, I’ve been more interested in its immunity-enhancing abilities, along with its role in athletic function, namely, skeletal muscle, lung function, heart function, and nervous system function, along with the possible role it plays in sexual function.

Regardless, I think they’re as wrong as a person or group of people can possibly be. They’re “We’ll never put a man on the moon” wrong.

Why my optimism in the face of such overwhelming statistics? Because the people who put together the study forget to consider a host of factors that determine whether vitamin D supplementation is effective or not.

Neglected Factor 1 – Magnesium

The study didn’t address magnesium intake at all, and vitamin D, regardless of how much you take, won’t do the things you need it to do if you’re deficient in magnesium.

Vitamin D just can’t be metabolized without sufficient magnesium. Without it, the vitamin just hangs around like some bum in front of a 7-Eleven.

Ordinarily, this magnesium issue might not be that important of a factor, but given that roughly 80% of the American public seems to be deficient in the mineral (according to the last NHANES study), it seems like it’s a really big deal and could explain why vitamin D3 supplementation didn’t appear to do squat in the VITAL study.

Oh, and athletes? They’re even worse off regarding magnesium, as the mineral is fond of leaving the body in sweat.

If you really want to figure out if vitamin D is doing the things it’s purported to do, you’ve also got to monitor magnesium intake. This fact alone might sink the veracity of the VITAL study.

Neglected Factor 2 – Magnesium’s Buddy, Calcium

Calcium and magnesium exist in a very tight relationship in the body. If this ratio isn’t respected, if something mucks it up – like a dramatic increase in the consumption of calcium foods without a concurrent increase in magnesium consumption – you get unfortunate consequences.

For one thing, you severely cripple the ability to transport, synthesize, and activate vitamin D.

Doctors and scientists see it all the time: Individuals with a high calcium to magnesium intake are at a higher risk of magnesium deficiency, and the activities of the three major enzymes that determine vitamin D concentrations are all magnesium dependent.

The result is a vitamin D deficiency, or at the very least, a vitamin D insufficiency.

So maybe you’re thinking, no problem, I’ll just double or triple-up my intake of vitamin D supplements. Not so fast.

The more vitamin D you take, the further you tap into magnesium stores, leaving you an increasingly insufficient amount to activate the enzymes responsible for determining vitamin D levels.

The problem is that calcium consumption, in-between the years 1977 to 2012 (the most recent dates for which we have data), increased at a rate 2 to 2.5 times that of magnesium intake, resulting in calcium to magnesium intake ratios of more than 3.0.

That’s understandable, given that the magnesium status is low in populations that consume a lot of processed foods that are high in fat, sugar, and refined grains.

The ideal ratio, however, is around 2.0 to 2.2, and anything higher than 2.8 can lead to problems, among them being the inability to metabolize vitamin D, not to mention a greater risk of developing type 2 diabetes, metabolic syndrome, chronic pulmonary disease, possibly some cancers, and impairing many of the 300 enzymatic reactions that involve magnesium.

Neglected Factor 3 – Fat Intake

Vitamin D3 is fat soluble. Without concurrently ingesting some fat, taking a vitamin D3 capsule won’t do much at all.

This problem is demonstrated by one of the dairy industry’s practices. To comply with the wishes of their customers and well-meaning dietitians, dairy companies remove much of the fat from their products (for example, low-fat milk, skim milk, etc.). However, removing the fat also removes the fat-soluble vitamin D, so they fortify their products by adding back some vitamin D.

However, since the fortified product doesn’t contain much fat, the body fails to absorb appreciable amounts of it. The unabsorbed vitamin D is like the impoverished child pressing its nose against the windowpane, able only to watch in envy as all the other nutrients get absorbed into the toy store of the intestinal tract.

The same thing is likely to happen with taking vitamin D capsules. Without taking them with a fatty meal, they won’t get absorbed efficiently. Subsequently, researchers will assume that the vitamin didn’t work.

Neglected Factor 4 – Difficulty Elevating Vitamin D Levels


I’ve seen it repeatedly and even experienced it personally. You take the initiative and try to elevate your vitamin D levels to optimal blood levels and start popping conventional capsules and grimacing down sardines for weeks or even months, and nothing much happens. Levels don’t budge.

The trouble is, the total amount of vitamin D (both D2 and D3) found in a food during chemical analyses often doesn’t reflect its bioavailability. A lot of the vitamin is bound up in the actual food and remains so after you eat it. Lots of things contribute to this: the physiochemical form of the vitamin D, the fatty acids and fibers in the food, the size of the food particles themselves, and the quantity of the vitamin itself.

Interactions between vitamin D and other fat-soluble nutrients might also be a factor, as well as a bunch of host-related issues (age, disease state, fed condition, genetics, obesity, etc.).

Then there’s how you might prepare any vitamin-D-containing foods. Heat affects it. Light affects it. Moisture, oxygen exposure, and even storage conditions affect levels of vitamin D. That means that any vitamin-D-containing foods that are boiled, pressure-cooked, Insta-Potted, baked, or air fried could end up being vitamin-D compromised.

Sure, the VITAL study didn’t discuss food sources of vitamin D, but traditional vitamin D supplements are prone to all the same manufacturing and absorption problems attributed to vitamin-D-containing foods – moisture, oxygen exposure, excess heat, and non-optimal storage conditions in general.

Unless all the above-listed precautions were taken in preparing and distributing the vitamin D used in the study, there’s sufficient reason to think that the capsules they used were the 3.2 beer of the vitamin D world. In other words, you’d need to ingest more than usual to get a vitamin D “buzz,” i.e., a protective effect.

What They Should Have Used Instead

The only form of vitamin D currently worth taking is microencapsulated vitamin D3. This form of the vitamin is manufactured by encapsulating vitamin D molecules in liposomes, or solid lipid nanoparticles.

The vitamin then presents as tiny “beadlets” and is protected from moisture, oxidation, pH, temperature, and mechanical forces. The microencapsulated product is stable, water dispersible, and, most importantly, highly bioavailable.

Studies show that the effects of this form of vitamin D remain constant for up to 14 days, making it clearly superior to the conventional vitamin D supplements that comprise most of the market. People who use it have reported rapid and impressive increases in blood levels of vitamin D.

However, as stressed above, you still need to have adequate levels of magnesium for it, or any form of vitamin D, to work. Given how difficult it is to obtain and maintain adequate levels of magnesium through diet alone, it seems prudent to pop at least 400 mg. a day, preferably in chelated form.

My Closing Argument

I’m still dumbstruck at how the VITAL study seemed to totally ignore the vast amounts of research on vitamin D and immunity, let alone all its positive effects on health and performance.

The simple fact is that infection-fighting T cells need vitamin D to activate. Researcher Carsten Geisler explained it this way:

“When a T cell is exposed to a foreign pathogen, it extends a signaling device or ‘antenna’ known as a vitamin D receptor, with which it searches for vitamin D. This means the T cells must have vitamin D or activation of the cell will cease.”

There’s also strong epidemiological evidence that people who live closer to the equator generally have fewer incidences of disease and better prognoses when they do get sick than people who live farther away from the equator. That’s because exposure to sunlight prods the body into making more vitamin D.

Further, assorted studies point to the strong possibility that once your vitamin D levels get beyond, say, around 50 mg per ml of blood (“normal” is considered to be around 20 mg per ml.), you’re practically immune to certain viruses.

I could go on for pages, but to reduce my argument to the simplest terms possible, our immune system needs vitamin D to function properly, and there are currently too many obstacles for people to get the amount they need.

So if you really want to conduct a quality study that tests the efficacy of vitamin D supplements, you’ve got to take into consideration all the factors I mentioned, not just toss them out into the world like giant handfuls of chicken feed.



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I take 1-2 4000IU Vit D tablets every day (depending on the season, time spent outside, etc) and they are definitely nowhere near the standard of BIOTEST stuff, not microencapsulated AFAIK. Comes from one of the biggest protein companies in the UK. Are they really not worth taking? I genuinely feel I have a better mood and drive when I am consistent with them.

Also on the subject of magnesium/calcium. I see criticism of them being taken together - I drink a lot of lactose-free milk and end up missing doses sometimes just because “i’ve had calcium”. I’ll plan to wait an hour to take my ZMA and end up forgetting.

No, you should still take them, but if you find out some day, courtesy of a blood test, that they haven’t driven up your serum D levels, make the switch. And yes, regarding taking calcium and magnesium at the same time, the bulk of the research seems to show that it’d be best to take them at different times.

Excellent article. So much new info for me.

I have high blood pressure and I am on medication to help control it. However, I also took an interest in lowering through diet and weight loss. I’m not obese, but probably 20% body fat. So, I know that’s a contributor as well as genetics. However, I have become obsessed with my diet. By making a few small changes, my food is naturally becoming more healthful and I am seeing results already.

I’m just added tracking magnesium and calcium to my small list of other things like potassium and sodium.

Im not totally sold that diet will fix my blood pressure. But I’ve taken it on as an experiment. It could be that I didn’t win the genetic lotto, and that’s just how it’s going to be. Either way, eating more healthfully will be a win-win.

Thanks again.

Cool! I find that taking an interest in the qualities of food makes eating a lot more satisfying. And yeah, a good diet is no guarantee against high blood pressure, but it just might drop down to an acceptable number if you get closer to 15% body fat. Godspeed.

Great article. I never thought the VITAL study made any sense, especially given that I am in the target group. My experience with D3 supplements is that they hands down contribute, but that is just evidence-based and single-sample anecdotal evidence.

I will point out that the Swedes are a lot smarter than we are when it comes to supplements and the study of them. I started taking a BioGaia product called Osfortis with Vitamin D. I was after the ATCC PTA 6475 that they have a patent on. This product is marketed to women for bone health. That said, let me tell you a little secret. MIT researchers found that when a man takes ATCC PTA 6475 it makes your balls swell; i.e., “restores testicular mass and other indicators typical of old age were similarly restored to youthful levels.” Now it won’t work if you are a twenty-something, but as men age their balls shrink, period. I wondered about the D3 that is included in Osfortis, but after this article it is clear why it is there. [quick disclaimer: the MIT study was on mice, but I am not the only one to see results].

This stuff works very quickly, but the effects start to fade a few days after you stop taking it. I think it is like creatine for the balls. All I know is that the old jock pouch (yeah, I am old school) is a lot fuller lately.

That was our original slogan, but the party poops in marketing nixed it. Anyhow, there’s plenty of research that shows vitamin D restores testicular function or vitality in those that are deficient, so it’s not inconceivable that it would make the testicles heftier too. Keep on swingin’.

Years ago I had a blood panel taken and my doctor suggested I stopped taking vitamin D supplements as mine was way too high. I assume that means it was working for me. During that time I also did a lot work outdoors with a lot of sun exposure. So you could also argue that the test result was from the Sun and not from the supplements or maybe both!


Remember, though, that most docs go by the traditional lab values. To them, anything over 30 ng/dl is high, but many nutrition experts recommend 50 ng/ml, or even higher.

I am 66 and in fairly good shape for my age but last year I was diagnosed with high blood pressure. When I was tested it was 180/100 but i when I test myself at home it’s at least 20 points lower. I discovered that in a doctor’s office it’s probably the worse place to take your blood pressure as you often experience the white coat syndrome where just the thought of being tested by a doctor or nurses your mind starts racing for the worse scenario.

Plus most nurses don’t know how to take proper blood pressure, you must be relaxed with your feet firmly on the ground, you must empty your bladder or any solids first and your back should be tested against the chair, the blood pressure arm should be elevated at the level as the heart while being propped on something like a cushion or pillow. And I would take three times for an average. The doctor prescribed me a blood pressure medication that derives from snake poison, after six weeks on constant coughing as a result of the side effects I decided to use the natural approach using very specific supplements that you rarely see advertised and I am fine now. By the way I almost quit the caffeine and alcohol as both constrict the arteries.

I agree. Most test for certain elevated markers are bogus including free testosterone which mine was highly elevated at 55.5 but I noticed next to the result it said “ it has not been cleared or approved by the FDA” imagine that. My Cholesterol is also high above 300 and I believe there is a direct relationship between high cholesterol and high testosterone. All my life my cholesterol has been over 200 and I refuse to take medication. I am now 66 and still training every day and taking the appropriate herbal supplements.

Same thing happens to me. Here’s an article I wrote about all the possible pitfalls: Tip: Don't Fall Prey To This Medical Mistake

Interesting study on resistance training you might like TC.

This article shows why you should get your vitamin D from sun exposure rather than rely on a supplement.

Vitamin D3 supplementation works, period. I have years of bloodwork you prove it. There’s something that needs to be mentioned, however. Vitamin D supplementation without adequate vitamin K2 can and will lead to heart and joint calcification. I also have the testing to prove this, unfortunately.

Ideally you get both types of vitamins from natural sources - in the case of D, the sun, and in the case of K, diet - but both can be supplemented. I urge you to do your own research to verify my statement as I’m not a doctor and I’m not providing medical advice. But, take this seriously…

Yes. Thanks!

It’s not possible for everyone to do that all year long, even if they could stand the cold. The sun isn’t sufficiently strong in those latitudes.

Very interesting because my Dr. literally just told me to take a Vitamin D supplement

So when vitamin D supplements raise your vitamin D levels it somehow doesn’t matter or so anything?