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HEALTH SENSE

The fading allure of vitamins

My love affair with vitamins and supplements is over: With a few exceptions -- stay tuned -- I'm tossing them out.

Things started going south for this romance 13 years ago when a Finnish study of 29,000 male smokers showed a higher rate of lung cancer in men who took beta-carotene and vitamin E and, more shockingly, found that those who took beta-carotene had an 8 percent higher risk of death from all causes. Two years later, an American study reported similar findings for beta-carotene.

I've never been a smoker, but a red flag is a red flag. Out went the beta-carotene.

Then came the bad news on vitamin E, for which I had had high hopes as a general disease-preventer. A 2004 analysis by Dr. Edgar R. Miller, of Johns Hopkins University, found an increase in deaths from all causes in people taking more than 400 International Units a day of vitamin E. In 2005, the Women's Health Study of nearly 40,000 healthy women showed 600 international units of vitamin E taken every other day provided no overall benefit for heart disease or cancer.

Out went the vitamin E.

Along the way, I tossed my echinacea, which I once swore by for preventing or shortening the duration of colds. (Never underestimate the placebo effect!) Though proponents still contend the studies are flawed, I now believe the debunkers -- among them the researchers who published a major study in 2005 in the New England Journal of Medicine showing that echinacea has no effect on colds.

Did I mention vitamin C? Oh, how I wanted to believe this famous antioxidant would keep me from getting cancer and all those colds! But despite numerous studies, "we haven't been able to show a benefit," Miller said.

The latest disillusionment came in February with a Danish study published in the Journal of the American Medical Association. When the researchers pooled the data from 47 reasonably unbiased studies involving 180,938 people, they found a 7 percent increased risk of death from all causes in those taking beta-carotene, a 16 percent increased risk of death in those taking vitamin A, and a 4 percent increased risk of death in those taking vitamin E.

Jeffrey Blumberg , a nutritionist and director of the antioxidants laboratory at Tufts University, among others, said that this study was based on flawed methodology, including the fact that the researchers left out of their analysis a number of studies that might have tipped the results in a different direction. But, to me, that's clearly not a strong endorsement of vitamins.

(An important caveat here: If I were at risk of developing advanced age-related macular degeneration, a leading cause of vision loss, I would talk with my doctor about taking vitamin C, E, beta-carotene, and zinc. A National Eye Institute study published in 2001 showed that this combination can slow progression of the disease. On the other hand, a study in March in the Archives of Ophthalmology showed no benefit to beta carotene pills alone.)

Multivitamins? Somehow, I can't part with mine yet, mostly because, try as I might, I still don't eat enough fruits and veggies. But my faith is slipping. A state-of-the-science conference sponsored by the National Institutes of Health synthesized data from a number of randomized, controlled trials, the gold standard of clinical research. In a paper published in 2006 in the Annals of Internal Medicine, the scientists concluded, disappointingly, that the "evidence is insufficient to prove the presence or absence of benefits from use of multivitamin or mineral supplements to prevent cancer and chronic disease." (For more, go to consensus.nih.gov.)

Adding to the speed at which the scales have been falling from my eyes is the latest news from ConsumerLab.com, a private company that tests vitamins, both for manufacturers and consumers.

ConsumerLab reported in January that 52 percent of the multivitamins it examined were contaminated with lead, didn't disintegrate properly, or had more or less of certain ingredients than indicated on the label. While Centrum Silver passed, a multivitamin called AARP Maturity flunked because it failed to disintegrate properly. (An AARP spokesperson said it believes "the validity of the ConsumerLab study is in serious question" and is therefore still "evaluating whether or not to continue to make the product available.")

A children's product called Yummi Bears Multivitamin and Mineral flunked, too, because it contained too much vitamin A, which can be toxic. (A spokeswoman for the company said other, independent tests show Yummi Bears products meet all label claims and that there is no basis for concern about vitamin A levels in the product.) Vitamin Shoppe Multivitamins for Women flunked because it had too much lead; a company spokesman said last week that the company has removed the product from stores.

So, what's left in my dietary supplement drawer?

Not much. Omega-3 fish oils, vitamin D, and calcium. Omega-3's are still on my "good" list because considerable research suggests they lower the risk of cardiovascular disease and abnormal heart rhythms. In ConsumerLab testing, omega-3 fish oils, thankfully, were found to be free of mercury, PCBs, and other potential contaminants. Vitamin D is still on my list because it helps protect against certain cancers and with absorption of calcium. Calcium is still there because it seems to help protect against bone loss, although recent research has raised some questions, so this might be next to go.

For me, the most pressing question now is how to have the most fun with the handful of twenties I'm not spending on supplements!

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