Doubts raised about vitamin E

By The Washington Post and Los Angeles Times

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High doses of vitamin E, which millions of people take with a belief that it protects them against heart attacks, Alzheimer's disease and other ills, appear to increase the overall risk of dying earlier, researchers said yesterday.

A new analysis of data from 19 studies involving 135,967 patients found that the increased risk of premature death was small, about 5 percent for those who had taken larger doses of the vitamin for at least five years. But vitamin E is taken by so many people — an estimated one-quarter of the U.S. population — that even a small increase is significant, researchers said.

"People take vitamins because they believe it will benefit their health in the long term and prolong life," said Dr. Edgar Miller of the Johns Hopkins University School of Medicine, a co-author of the study. "But our study shows that use of high-dose vitamin E supplements certainly did not prolong life, but was associated with a higher risk of death."

Miller presented the results yesterday at a New Orleans meeting of the American Heart Association, and they were simultaneously published online in the Archives of Internal Medicine.

"Too often, in terms of the supplements, there's very scant science," Dr. Raymond Gibbons of the Mayo Clinic told a news conference at the heart meeting. "In this area, we have the science. Vitamin E doesn't work."

Some scientists were skeptical of the findings. Dr. David Heber, director of the University of California, Los Angeles, Center for Human Nutrition, noted that there is "a disconnect" between large studies such as this one and smaller studies that have shown a benefit from taking vitamin E.

Many people in the studies "were older people and had pre-existing diseases," he said. "It's hard to ascribe the bad outcomes to vitamin E, per se."

The new results indicated an increased risk for patients — most of whom were older than 60 and who had heart disease or other illnesses — who took more than 400 international units (IU) of vitamin E a day. Vitamin E supplement capsules typically contain 400 to 800 IU, and some contain as much as 1,000. Multivitamin supplements typically contain 30 to 60 IU.

The results do not say anything about the effects of high doses in older people who are healthy or the effects in younger people. The study also found no increased risk at doses less than 200 IU, and possibly a slight benefit.

Most people receive 6 to 10 IU of vitamin E a day from their diet, typically from vegetable oils, green leafy vegetables, and seeds, nuts and corn.
 
The findings are the latest in a series of recent findings undermining the theory that anti-oxidant substances may provide powerful protection against a variety of illnesses by preventing unstable oxygen molecules known as free radicals from damaging DNA. That has prompted many people to take supplements containing high doses of anti-oxidants, including vitamin E.

In 2003, Americans spent $710 million on vitamin E, making it the second-most-popular individual vitamin behind vitamin C, according to the Nutrition Business Journal, which tracks industry trends. Federal nutritional guidelines do not recommend vitamin E supplementation but state that doses of up to 1,000 IU a day are safe. Based on the findings, Miller and his colleagues recommended the upper limits be re-evaluated.

Although the study did not examine how high-dose vitamin E might increase the risk of premature death, other studies have suggested the substance may boost the danger of heart attacks and strokes, perhaps by affecting blood clotting or blocking beneficial effects of other nutrients, researchers said.

Many cardiologists and the American Heart Association recommend that patients not take vitamin E because previous studies have shown the supplements are not beneficial.

Vitamin E manufacturers and proponents scoffed at the new findings.

John Hathcock, vice president of scientific affairs for the Council for Responsible Nutrition, a supplement-industry group, said the increased risk found by the study was "driven by the results from just a few of these clinical trials, some of which are suspect and/or outdated."

"This is an unfortunate misdirection of science ... for the sake of headlines," he said.

Leiner Health Products of Carson, Calif., which manufactures more than half the private-label vitamin E sold in the United States, dismissed the study as "scientific folly."

"We were pretty dismayed that a reputable university like Johns Hopkins would come out with something so misguided," Leiner spokeswoman Crystal Wright said.