To Your Health
Update on Vitamin D

by Paulette Avery RN, MSN

In the May 2004 issue, I wrote about vitamin D deficiency and recommended getting adequate sun exposure to increase your natural vitamin D production. Based on the latest research, that remains good advice. But you may need to do more, at least at this time of the year, to get and maintain adequate levels of Vitamin D.

An article dated December 29, 2005, on the Web site of the American Cancer Society reports on recent studies that suggest that adequate levels of vitamin D may help to prevent colon, breast, and ovarian cancer. In two articles published by researchers at the University of California, San Diego, a review of many studies on vitamin D indicates that people who are deficient in it are more likely to develop cancer. The studies also found that taking 1,000 mg/day of supplemental vitamin D can reduce the risk of colon cancer by 50 percent. Other studies on vitamin D suggest a lowered risk of developing colon, breast, ovarian, and prostate cancer in people with higher levels of vitamin D in their bodies.

How do we get enough vitamin D? According to Dr. John Cannell, founder of the Vitamin D Council, the best way to get vitamin D is through sun exposure. During the spring, summer, and fall he recommends getting 20 minutes of unprotected sun exposure a day, which will generate 20,000 units of vitamin D. In the winter, take up to 2,000 units (the safe upper intake level) a day as a supplement, specifically cholecalciferol, also known as vitamin D3.

As explained by Richard Harkness, a syndicated nutrition columnist, in a recent article, D3 is one of two forms of vitamin D, the other being D2. D2 comes from plant sources and is the type found in D-fortified products such as milk and cereal. D3 is the form produced by our bodies when skin is exposed to sunlight. Both types of D convert to vitamin D in our bodies, but D3 is three times as potent as D2. You can find vitamin D supplements in the form of cholecalciferol at most health food stores or over the Internet.

In addition to helping to prevent cancer, preliminary studies indicate that higher levels of vitamin D may also be useful in the treatment of cancer, although Dr. Cannell advises that vitamin D should never be used as a substitute for standard cancer treatments. Vitamin D also plays an important role in the prevention of many other diseases such as hypertension, diabetes, multiple sclerosis, arthritis, and depression.

As a lactation consultant, I was intrigued to find while researching this column that breastfeeding mothers may need at least 3,600 units/day of vitamin D to maintain adequate blood levels of vitamin D for themselves and their babies. When lactating mothers took this much vitamin D, researchers Hollis and Wagner at the University of South Carolina found that they were able to maintain bone density much better than mothers who did not supplement at all or even those who supplemented with as much as 2,000 units/day of D3. Until this finding, it was believed that loss of bone density during breastfeeding was a normal, although unfortunate consequence of the process. Since vitamin D deficiency and a rise in the occurrence of rickets in breast-fed infants has been in the news in the past couple of years, I will certainly be advising my colleagues and patients of the need for adequate supplementation.

For further information on this topic I recommend the Web site www.cholecalciferol-council.com. Meanwhile, get unprotected sun exposure a few minutes a day whenever you can, and start taking 1000-2000 units a day of cholecalciferol. That's what I plan to do.

Paulette Avery is a registered nurse and a freelance writer specializing in health issues.