Monday, January 12, 2009

E BAD, D GOOD

Many of us doctors have spent years hoping that vitamin E turned out to have some health benefits. Why? I'm not really sure. Maybe because it's cheap, it's an "antioxidant," and it comes in those cool-looking little gel-filled capsules that are easy to swallow. What is amazing is that despite the fact that vitamin E is not profitable for any drug company, more research money has been poured into vitamin E studies than into studies of many of our most widely prescribed drugs and nutritional supplements. In total, there are in excess of 100 high-quality research trials involving vitamin E, many of them using thousands of patients taking vitamin E for years.
The results? Vitamin E has been found to help with NOT ONE GOD DAMNED THING. Given the fact that it is an antioxidant, it was thought that sooner or later, it would turn out to reduce the incidence of heart attacks, or at least a cancer or two. No such luck. In massive studies, vitamin E not only did not prevent heart attacks, but it (very slightly) increased the risk of stroke. Men taking vitamin E for years did not get any less prostate cancer or lung cancer- in fact, the vitamin E takers seemed to get more cancers, though the effects were small. The vitamin has also been shown to do nothing substantial to extend lifespan, reduce the effects of Alzheimer's disease, or improve vision. As my favorite source The UC Berkeley Wellness Letter
states in regard to vitamin E, "when hundreds of studies fail to find a benefit, and so many contradictions emerge, you have to be skeptical." Furthermore, vitamin E deficiency is so rare as to be almost unheard of, even in poor countries where malnutrition is a serious problem.
The bottom line: please don't waste your money taking vitamin E supplements.

WHAT ABOUT VITAMIN D?
You may have heard that you can get vitamin D from milk and other dairy products, and that your skin also makes this vitamin when you spend time in the sun. This is true. Even soy milk and many brands of orange juice are now fortified with vitamin D. So what? Well, it turns out the vitamin D DOES prevent diseases, notably osteoporosis. It also strengthens bones even if you aren't so unlucky as to have osteoporosis. In studies of frail seniors, vitamin D has been found to reduce the risk of falls- we don't know how this works, but the vitamin may have a role in balance and stability. As for osteoporosis, it's generally thought of as a disease that old women get; in fact, bone loss can begin at any age, especially if you are not getting enough vitamin D. Unlike vitamin E deficiency, vitamin D deficiency is rampant. In my clinic, over 30% of patients tested for vitamin D levels have turned out to be deficient in this vitamin, and I'm testing people of all ages.

DO I NEED TO TAKE VITAMIN D?
If dairy products are a major food source in your diet, and if you spend on average 10 minutes or more per day out in the sun (even WITH sunscreen), you probably get enough vitamin D. It rarely hurts to supplement with this vitamin, however; the exception is people who get frequent kidney stones, who should speak to their doctor before taking vitamin D. If you don't eat dairy products, it's a very good idea to take vitamin D. The recommended amount will likely go up as more research is done- for now, most doctors say to take 800-1200 IU (international units) per day. It's also worth asking your doctor to test your vitamin D level if you rarely go out in the sun, rarely eat dairy, or have family members with osteoporosis. It's a relatively inexpensive and easy test which just requires a small blood sample. An easy way to make sure you're getting enough vitamin D and calcium, which also helps bone strength, is to take one of the many combined "calcium + D" supplements that contain both these nutrients.

Finally: watch the media in regard to vitamin D. A lot of exciting research is going on with this vitamin; perhaps because we're done wasting money on vitamin E research...