A Little Vitamin D Can Do a Lot of Good

It is simply not possible anymore to pick up a newspaper or turn on the television or especially to prowl the Internet without being confronted with incredible hype for this supplement or that dietary miracle. The magic bullet theory of health promotion is very seductive, and no one can be faulted for wanting it to be true. However, sometimes it's just nice to talk about the less glamorous but more useful world of things that actually have been extensively studied and seem to be what they claim to be.

Last year, some extremely preliminary research on vitamin D and various forms of cancer got everybody all excited about vitamin D supplements, even though vitamin D is one of those substances that can be toxic when taken at high levels (over 2,000 international units a day). And nearly all the known cases of vitamin D toxicity have been related to supplement intake.

Vitamin D is a hormone manufactured by the body to help with the utilization of calcium and phosphorous. In that role, it helps to build bones and teeth and probably has a good effect on the immune system. In children, a vitamin D deficiency can cause a condition known as rickets, in which the bones don't form properly. In adults, a deficiency may contribute to osteoporosis.

Interestingly, most people don't even need to get their daily requirement of vitamin D from food, since it is manufactured by skin cells exposed to sunlight. And it doesn't take very much sunlight either. Ten to 15 minutes of sun on your arms and face two or three times a week is all that most people really need, because vitamin D is fat soluble and can be stored in the body for months when you don't get any sun.

In the good news-bad news department, sunscreen, which, of course, helps protect against skin cancer, may also keep the body from producing enough vitamin D.

*

The people who are most likely to be deficient in vitamin D are those who are housebound and get little sun; vegans, who eat no animal products; and elderly people who may not get out much and also tend not to drink milk. Also, those with darker complexions (who need longer sun exposure to get enough vitamin D) or who live in northern areas, where sunlight is scarce in the winter and temperatures require layers and layers of clothes, really need to make sure that they get enough vitamin D somewhere else.

A good multivitamin is sufficient to ensure your needs. It is almost impossible to get too much vitamin D from a combination of sunlight, food and a multivitamin.