Optimizing vitamins B1, B3, C and D prevents cavities and anorexia. Read more here. Prevention of cavities is associated with reduced risk of a whole host of modern chronic diseases including cancer, heart disease, obesity, and diabetes. Read more here.

Vitamins A, B1, B3, C and D are special because they are the only four vitamins associated with named vitamin deficiency diseases. These are night blindness, beriberi, pellegra, scurvy, and rickets respectively.

A clear understanding of the state of knowledge regarding the clinical use of these five vitamins makes it easier for literate people to use them. Unfortunately, writings about vitamin D – even from the most authoritative sources – are filled with misinformation.

The misinformation from the mainstream medical community is largely one of omission. Overwhelming evidence has proven that the R.D.A of vitamin D of 400 IU is too low, yet the R.D.A. has not been raised. The R.D.A. really relates to vitamin D obtained from food. The mainstream medical community is largely silent regarding recommendations for generating vitamin D in the skin via exposure to sunshine. There are no warning labels about the dangers of sunblock, and the dangers coming from the multiple ways modern life results in inadequate sun exposure. For example, working night shifts, working underground, wearing a habit all the time, staying indoors all the time, and on and on. On the contrary, mainstream medicine warns people about the dangers of sunshine and markets sunblock lotions as safe and effective.

Mainstream medicine is also guilty of misdirection. Vitamin D is not a vitamin. It is not an essential nutrient. It is not necessary to eat any because vitamin D is produced in the body from ordinary food combined with skin exposure to direct sunlight. With few exceptions, humans evolved to produce vitamin D in their skin. Sunshine is essential for good health. Using pills instead of sunshine is asking for trouble.

Vitamin D boosters are doing a great job setting the record straight regarding the misinformation from the medical community. But vitamin D boosters are responsible for misinformation of their own. There is a reluctance to take the toxicity of vitamin D seriously. Here’s a typical quote (read the whole entry here) denying the toxicity of vitamin D:

“Without evidence to support it, the board arbitrarily set the safe upper limit for vitamin D consumption at 2,000 IU/day. One can take a 10,000 IU vitamin D supplement every day, month after month safely, with no evidence of adverse effect. (Am J Clin Nutr 1999;69:842–856).”

Well that’s just great. And even worse it’s supported by an authoritative reference in a peer reviewed journal. Wonderful. There is overwhelming clinical evidence that daily vitamin D doses above 2000 IU cause side effects. I have written about this in detail here. My column on vitamin D toxicity attracted compelling testimony about the harm being caused by vitamin D supplements. Evidently I’m a very unusual scientist since I’m able to fully appreciate both the benefits and the risks from the use of vitamin D supplements.

Here’s the second major piece of misinformation spread mostly by vitamin D boosters. It is claimed that there is inadequate solar radiation to produce vitamin D in the winter. The same article contains a typical quote:

“The majority of the world’s population now lives above latitude 35° N and is unable to synthesize vitamin D from sunlight for a period of time in winter owing to the angle of the sun. At a large solar zenith angle, ozone in the upper atmosphere will completely block UVB radiation. In Seattle (47° N) and London (52° N), from October to April UVB photons are blocked by the atmosphere so one’s skin cannot make vitamin D.”

I can rebut this argument on first principles. If UVB makes it through the ozone layer in the summer, increasing the pathlength of the light through the upper atmosphere by less than a factor of ten (what happens in the winter), will not completely block the radiation. It may reduce the UVB by a factor of ten, or even a factor of 50, but it will not block it altogether. How much UVB is really needed? The objective is to produce just 25 micrograms of vitamin D. Getting out into the winter sun at noon in northern latitudes with the shirt off for an hour is highly likely to produce plenty of vitamin D. I’m not going to believe this nonsense until I’m provided with much better data. Amazingly, I’ve been unable to find good data on this subject.

Vitamin D is vitally important to health. It’s long past time to increase funding for vitamin D research and to clear up all this misinformation.