Prize winning sites , Telomeres, and living to 1,000
Science magazine is now selecting prize winning web sites that explain science clearly. The first prize winner is Learn.genetics. An essay that fascinated me explains telomeres in the context of aging and cancer, including the role of free radicals, causing oxidative stress, and glycation, causing wrinkles, both of which occur more slowly as we get antioxidants in our diets. Read about telomeres and aging here.
VITAMIN D, MIRACLE DRUG?
The New York Times of February 1, 2010, ran an article titled “Vitamin D: Miracle Drug: Is it science, or just talk?” The author writes, “But don’t start gobbling down vitamin D supplements just yet. The excitement about their health potential is still far ahead of the science. Although numerous studies have been promising, there are scant data from randomized clinical trials. Little is known about what the ideal level of vitamin D really is, whether raising it can improve health, and what potential side effects are caused by high doses.“ The author adds many short quotations from distinguished scientists. Having been similarly quoted in the past, I know how such statements may not represent the scientist’s view. After reading that article, concerned friends have asked me whether taking vitamin D supplements is worthwhile. Here is my response based on years of reading peer-reviewed scientific literature about vitamin D. YES.
The scientific and nutritional literature strongly advocates getting 1,000 to 2,000 IU of vitamin D daily. Since 2002, I have been quoting Michael Holick, the scientist who chaired the Federal panel that established the vitamn D level at 400 IU in 2000. Since that time, he has been telling everyone, and writing peer-reviewed scientific articles, stating that the level now should be from 1,000 to 2,000 IU daily. Contrary to the New York Times story, his claim is based on solid science. A review of that evidence published in 2009 is here .
Four hundred and fifty five peer-reviewed papers on vitamin D were published in AJCN and the Joural of Nutrition in 2009 alone, all describing benefits of high vitamin D levels. Now we have the ability to determine gene (DNA) and protein expression levels in cells and people. We can determine the effects of particular nutrients on our metabolism, and their signaling mechanisms that control genes and hormone levels. The effects are profound and, in the case of vitamin D, very beneficial. Here is a summary of his remarks in May of 2009:
VITAMIN D – 50% of the US is deficient in D. Vitamin D affects depression, preeclampsia, hypertension, and immune function. Obesity decreases 45% with adequate vitamin D! Strength and balance are both proportional to vitamin D status. The risk of having a C-section is 400% greater in women with vitamin D deficiency. Breast milk contains only 10% of the vitamin D consumed by the mother. Nursing infants need 400 IU daily for full growth, so mother should take 4,000 IU or give the baby a 400 IU supplement. For psoriasis, treating the skin with vitamin D mixed into Vaseline is likely to provide great relief.
Note the Upper limit for vitamin D, set by a panel of nutrition experts to be absolutely safe, was 2,000 IU in 2000, but a newer risk assessment published in 2007 raised that safety level to 10,000 IU.
GETTING IT FROM SUNSHINE: The skin produces approximately 10,000 IU of vitamin D in response 20–30 minutes of summer sun exposure in a bathing suit. “Can I get too much vitamin D? You can’t get too much vitamin D from the sun or from eating foods that are high in vitamin D. However, taking too much of a vitamin D supplement can be harmful. Research has shown that the maximum amount of vitamin D a teen should get is 50 mcg or 2,000 IU, and the minimum is 10 mcg or 400 IU.” From the Center for Young Women’s Health
THE BOTTOM LINE: The information above, coupled with the many peer-reviewed references that can be found using the search command for this site, represents the weight of scientific evidence for getting 2,000 IU of vitamin D every day to maintain long-term health. Medical professionals presented with this are likely to accept that conclusion, which is advocated by the top Federal authority on vitamin D, Dr. Michael Holick.
