Tuesday, June 1, 2010

The Vitamin D Dilemma

Recently I was sent an article by one of our vendors on the trade-off between getting Vitamin D and potentially getting skin cancer. Since Melanoma Awareness Month is only just now over (as of yesterday), and since the sun is only going to get stronger as we move into the summer months, I thought I'd re-post what I wrote in my newsletter, which quoted large sections of the article:

In a nutshell, the vitamin D dilemma goes like this: if the sun is a good source of vitamin D, and we can suffer from vitamin D deficiency by not getting enough sun exposure, then shouldn't we be unafraid to spend 5-10 minutes getting unprotected UV exposure from either the sun or tanning machines 2-3 times a week?


Over the last several years, physicians and scientists have debated sun exposure as a beneficial source of Vitamin D. Many assert that vitamin D produced in the body can help prevent prostate, colon, breast, and other cancers, as well as bone diseases.

These scientists are worried that people are now at greater risk for these diseases because "dermatologists have scared them out of the sun." Most dermatologists and cancer groups (including the Skin Cancer Foundation), however, argue strongly against the solution of spending unprotected time in the sun or in UV tanning machines. And new analysis from the Department of Dermatology at the Boston University School of Medicine appears to support this stance.


After reviewing the massive research available on vitamin D and sun exposure, Drs. Dean Wolpowitz and Barbara Gilchrest found that in regions where people have greater sun exposure, fewer cases of colon cancer occur, and fewer deaths occur from colon, breast, and prostate cancers. Presumably, this is because of sun-induced vitamin D. However, Wolpowitz and Gilchrest contend that UV is an officially recognized environmental carcinogen, and that the more than 1.3 million people diagnosed annually in the U.S. with skin cancers qualifies as a "near epidemic." And the cause of most of these cases? Sun exposure.


In a word, NO. According to Wolpowitz and Gilchrest, the studies that support getting unprotected sun exposure are "observational" and "variable in quality." In general, the data links mortality from colon, breast, and prostate cancer from specific regions with the amounts of UV in those regions, but such studies can be muddled by climactic factors such as pollution, variations in population genetics (such as darker- or lighter-skinned populations), and cultural or lifestyle factors (socioeconomics and diet). Therefore, these studies cannot directly correlate disease with individual sun exposure.

By contrast, much research (ranging from animal studies to surveys to large population and human DNA studies) has strongly established the connection between sun exposure and skin cancer. Drs. Wolpowitz and Gilchrest note that very small amounts of sun exposure provide ALL the vitamin D the body can manufacture. They say that even when you're wearing sunscreen, some UV reaches the skin, and for fair-skinned individuals, this may be plenty. The doctors conclude that greater exposure to the sun does nothing for vitamin D stores, but does increase DNA damage in a linear fashion. Their bottom line? The tradeoff of vitamin D production for photoaging and skin cancer does not make sense.

At Pavia, we like to recommend Colorescience's Sunforgettable powder sunscreens, which come in 3 shades, are SPF 30, easy to apply, water-resistant, and have received FDA approval as well as the Seal of Recommendation from the Skin Cancer Foundation of America.


Fortunately, there are effective and almost effortless sources of vitamin D - that are also non-carcinogenic. These include vitamin D supplements and vitamin D-fortified foods. For example, I like to take 4,000 IUs of vitamin D from a supplement supplied by my holistic physician, Dr. Kim Millman. You can also drink vitamin D-fortified orange juice or eat salmon and other fatty fish. There's even a vitamin D oral spray from Dr. Mercola, found here. And all of this is so much easier and safer than climbing into a tanning booth or laying out and frying our whole bodies in the sun.

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