Carey, Vitamin D to the rescue

This article from Newsweek magazine discusses vitamin D, a vitamin once thought to be “boring” by doctors but has now been found to have dramatic positive effects on the human body, even though the majority of the population doesn’t get nearly enough of it. When it was discovered a century ago, vitamin D was used to cure a major public health problem: the disease rickets, which was caused by vitamin D deficiency and led to slow bone development. With the intake of the vitamin, the problem of rickets disappeared, so doctors advised that the RDA (recommended daily allowance) was simply the level that would prevent rickets. Today, however, the health problems linked to vitamin D deficiency are more serious: type I diabetes, multiple sclerosis, tuberculosis, colon cancer, and the flu. Conversely, high levels of vitamin D can help fight the HIV infection, as well as protect against fractures in adults by strengthening bones and muscles. The main problem in combating vitamin D deficiency is that it is only found in a few foods, and we get most of it from sunlight shining on our skin. Modern life makes this method of intake difficult, as we spend a lot more time indoors than our ancestors did, as well as wear more clothes and use more sunscreen. Sunscreen, when applied to protect against skin cancer, can actually lower skin’s ability to make vitamin D by 95 percent. Age, obesity, the time of sun exposure, the season, and geography also all affect how much vitamin D your body can produce. Skin pigmentation can affect the way your body processes vitamin D as well, because melanin, the pigment that provides a darker tint in the skin, acts as a sunscreen, so darker-skinned people require at least five times as much sun exposure to form the same amount of vitamin D that a fair-skinned person has.

So what do we do to ensure that our bodies are getting adequate amounts of this vitamin? There are only three ways to take action: increase sun exposure, increase our intake of foods rich in vitamin D, or take vitamin D supplements. Considering the threat of skin cancer and the lack of vitamin D-rich foods (fatty fish, some mushrooms, and fortified dairy products), the third option seems to be the most practical. Doctors agree that the current RDA of 400 IU is too low and should be raised to around 1,000 IU, or perhaps even higher for people over the age of 70 or those that live in northern regions with less sunlight (a cup of milk has 100 IU). Even though our body needs vitamin D, too much can be toxic; the current official upper limit is 2,000 IU, but many experts think this should be raised to 4,000 IU.

•IU – An international unit (IU) is an internationally accepted amount of a substance. This type of measure is used for the fat-soluble vitamins (such as vitamins A, D and E) and certain hormones, enzymes, and biologicals (such as vaccines).

I chose this article as I was searching the Newsweek website for pieces on vitamins because I did not know much about vitamin D, perhaps because until only recently, there was not much press about it. After reading this article, I think the suggested course of action of taking supplements sounds like a good idea, especially if someone like me, who is fair-skinned but wears a lot of sunscreen, is to get a proper intake of this helpful vitamin.

Stampfer, Meir J., M.D., DR. P.H. "Vitamin D in the Spotlight." Newsweek 15 Oct. 2007. 16 Feb. 2008
http://www.newsweek.com/id/43998/page/1