WORLD / Health |
Antioxidants don't help you live longer(AP)Updated: 2007-02-28 09:19 CHICAGO - Antioxidant vitamins taken by tens of millions of people around the world won't lead to a longer life, according to an analysis of dozens of studies that adds to evidence questioning the value of the popular supplements. The large review of separate studies on thousands of people found no long-life benefit from vitamins A, E and C and beta carotene and selenium.
However, some experts said it's too early to toss out all vitamin pills - or the possibility that they may have some health benefits. Others said the study supports the theory that antioxidants work best when they are consumed in food rather than pills. An estimated 80 million to 160 million people take antioxidants in North America and Europe, about 10 to 20 percent of adults, the study's authors said. And last year, Americans spent $2.3 billion on nutritional supplements and vitamins at grocery stores, drug stores and retail outlets, excluding Wal-Mart, according to Information Resources Inc., which tracks sales. The new study, appearing in Wednesday's Journal of the American Medical Association, was led by the Cochrane Hepato-Biliary Group at Copenhagen University Hospital in Denmark. The Cochrane organization is a respected international network of experts that does systematic reviews of scientific evidence on health interventions. For the new report on antioxidants, the researchers first analyzed 68 studies involving 232,606 people and found no significant effect on mortality - neither good nor bad - linked to taking antioxidants. When they eliminated the lower-quality studies and looked only at the most trustworthy ones, they actually found a higher risk of death for people taking vitamins: 4 percent for those taking vitamin E, 7 percent for beta carotene and 16 percent for vitamin A. The actual cause of death in most studies was unknown, however. Those findings are based on an analysis of 47 studies involving 180,938 people who were randomly assigned to get real vitamins or dummy pills. Some involved superdoses far exceeding the recommended daily amount of the compounds; others involved normal doses. Some experts who reviewed the research were dismissive of the increased death risk and the analysis overall, saying it pooled studies that were too diverse. However, the study's senior author, Dr. Christian Gluud of Copenhagen University Hospital, said, "The main message is that prevention by beta carotene, vitamin A and vitamin E cannot be recommended. These three antioxidant supplements may increase mortality." Gluud said most of the studies didn't reveal why those taking supplements died, but "in all likelihood, what they died from is what people normally die from, maybe accelerated artherosclerosis, maybe cancer."
ntioxidant supplements have been tested repeatedly by many clinical trials with no consistent clear evidence for their health effects, Gluud said. "We have had this huge industry really wanting to demonstrate an intervention
effect that has gone to lengths to do so," Gluud said. "Sadly enough for the
industry, and for us as consumers, it has failed to do so."
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