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Feb. 27, 2007 – Use of the popular antioxidant supplements beta-carotene, vitamin E, or vitamin A slightly increases a person's risk of death, an overview of human studies shows.
The study also shows no benefit -- and no harm -- for vitamin C supplements. Selenium supplements tended to very slightly reduce risk of death.
Oxidative stress -- caused by highly reactive "free radical" compounds circulating in the blood -- is a factor in most diseases.
Antioxidants sweep up these free radicals. It seems to be a no-brainer that taking antioxidant supplements would protect your health. But it may not be that simple.
A new, detailed analysis of human studies of beta-carotene, vitamin A, and vitamin E shows that people who take these antioxidant supplements don't live any longer than those who don't take them. In fact, those who take the supplements have an increased risk of death.
The finding, reported in TheJournal of the American Medical Association, comes from Goran Bjelakovic, MD, DrMedSci, of the University of Nis in Serbia; Christian Gluud, MD, DrMedSci, of Copenhagen University Hospital in Denmark; and colleagues.
"Our findings have already changed the way I counsel my patients about antioxidant supplements," Bjelakovic tells WebMD in an email interview. "According to our findings, beta-carotene, vitamin A, and vitamin E cannot be recommended. I am telling them that they should stop using these supplements."
"There is no reason to take anything that hasn't been proven beneficial. And these antioxidant supplements do not seem beneficial at all," Gluud tells WebMD.
Not everyone agrees. Nutritionist Andrew Shao, PhD, is vice president for scientific and regulatory affairs at the Council for Responsible Nutrition, a supplement-industry trade group.
"Consumers can feel confident in relying on their antioxidant supplements as they always have," Shao tells WebMD. "They can continue to take them knowing they will provide the same benefits -- and this article does not change that."