Vitamins C and E — pills taken by millions of Americans — do nothing to prevent heart disease in men, one of the largest and longest studies of these supplements has found (Yahoo! News).
Vitamin E even appeared to raise the risk of bleeding strokes, a danger seen in at least one earlier study.
About 12 percent of Americans take supplements of C and E despite growing evidence that these antioxidants do not prevent heart disease and may even be harmful.
Male smokers taking vitamin E had a higher rate of bleeding strokes in a previous study, and several others found no benefit for heart health.
As for vitamin C, some research suggests it may aid cancer, not fight it. A previous study in women at high risk of heart problems found it did not prevent heart attacks.
Few long-term studies have been done. The new one is the Physicians Health Study, led by Drs. Howard Sesso and J. Michael Gaziano of Harvard-affiliated Brigham and Women's Hospital in Boston (Yahoo! News).
It involved 14,641 male doctors, 50 or older, including 5 percent who had heart disease at the time the study started in 1997. They were put into four groups and given either vitamin E, vitamin C, both, or dummy pills. The dose of E was 400 international units every other day; C was 500 milligrams daily (Yahoo! News).
After an average of eight years, no difference was seen in the rates of heart attack, stroke or heart-related deaths among the groups.
However, 39 men taking E suffered bleeding strokes versus only 23 of the others, which works out to a 74 percent greater risk for vitamin-takers.
The study was funded by the National Institutes of Health and several vitamin makers. Results were so clear that they would be unlikely to change if the study were done in women, minorities, or with different formulations of the vitamins, Howard said (Yahoo! News).
"In these hard economic times, maybe we can save some money by not buying these supplements," she said.
Annette Dickinson, former president of the Council for Responsible Nutrition, a supplement industry group, says the findings point to the need to place supplements in a context in which consumers are also taking other steps toward a healthful life (USA TODAY).
"You pull a nutrient out of the whole diet context and you don't see the same effects," she says.
Dickinson says more research is needed to determine whether a higher dose or different form of vitamin E would be more effective.