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Vitamin E Loses Luster: Nutrient tests show disappointing results

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11:01am, March 16, 2005
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Is that the sound of gelcaps plunking into trash cans? It could be, after publication of a new study reporting that vitamin E supplements fail to promote overall health in older people at risk for heart problems and might even hike their chances of developing heart failure.

That's not the only recent count against vitamin E, an oily substance usually dispensed in clear capsules. Earlier this year, researchers at Johns Hopkins Medical Institutions in Baltimore reported finding a pattern in past studies of elderly people with health problems: Those taking vitamin E supplements had a slightly higher death rate than did participants getting a placebo, the scientists said in the Jan. 4 Annals of Internal Medicine.

In the new study, researchers in several countries recruited 9,541 people, average age 66, who had a history of either heart problems or diabetes, which is a major risk factor for heart disease. Half were randomly assigned to take natural vitamin E every day during the 7-year study. The others got an inert look-alike pill.

People getting vitamin E were 19 percent more likely to be admitted to a hospital for heart failure during the study than were those taking a placebo, the researchers report in the March 16 Journal of the American Medical Association.

The rates of death, stroke, heart attack, and cancer were similar for the two groups, says study coauthor Eva Lonn of McMaster University in Hamilton, Ontario.

Tests done in the early 1990s in animals had suggested that vitamin E, an antioxidant, could limit atherosclerosis, the accumulation of fatty plaques in blood vessels. Antioxidants mop up free radicals, which are molecular fragments that swipe electrons from nearby molecules. Seeking a replacement electron, these molecules begin a chain reaction that can damage or kill cells (Drink Those Antioxidants). Slowing this process with antioxidants, therefore, would seem to be a way of limiting plaque development in blood vessels.

Vitamin E supplements also seemed a good bet to fend off cancer. After all, antioxidants are known to limit cell damage, and a diet high in antioxidants has been associated with low cancer risk.

Why vitamin E didn't protect participants in these studies against cancer and heart disease is unclear.

Stephan Christen of the University of Berne in Switzerland says that the higher rate of heart failure in those elderly volunteers getting vitamin E "appears to be real and means that supplementation should not be used in this patient group."

But not everyone is ready to give up on vitamin E.

Simin Nikbin Meydani of Tufts University in Boston says that lower doses of vitamin E might offer health benefits without adding risks. In her tests (SN: 9/4/04, p. 157: Available to subscribers at Vitamin E may curb colds in old folks), older people developed fewer respiratory infections while taking half the amount of the vitamin E they received in Lonn's study.

She notes that many of the people in the new study were on medication for heart disease. "Maybe vitamin E increases degradation of some of the drugs these people take," she suggests.


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