Other reviews, published in prominent medical journals, suggested that antioxidants had no benefit for heart disease, and in certain patients even raised the risk of cancer and heart ills.
Such findings have been denounced by groups like the Council for Responsible Nutrition (CRN), a Washington, D.C.-based trade association representing ingredient suppliers and manufacturers in the dietary supplement industry.
Annette Dickinson, former president of CRN who now works as a consultant for the group, says the current review fails to take into account the positive findings of the studies it examined.
"One of the heart disease studies showed a 75 percent decrease in the risk of a second heart attack," she said. "And one of the studies on selenium was so positive that the National Cancer Institute is now suggesting a study of selenium on 35,000 men to see if it decreases the risk of prostate cancer."
Even several diet experts agreed that the design of the review may be too narrow to determine whether antioxidant supplements have other benefits unrelated to life expectancy alone.
"I have to agree with their conclusions, but I wonder about other confounders in the analysis," said Mary Beth Kavanagh, instructor in the department of nutrition at Case Western Reserve University in Cleveland. "Dietary intake of antioxidants and other nutrients is not usually studied along with the supplements. There may be synergistic effects between antioxidant nutrients and other bioactive components of food that are missed because of this."
"It's possible that the antioxidants here have their best application in the arena of prevention rather than of cure and life extension," said Keith-Thomas Ayoob, an associate professor of pediatrics at the Albert Einstein College of Medicine in New York.
For example, he said, it is possible that supplements may increase the quality of life for people with chronic conditions such as diabetes, even if they do not necessarily extend life expectancy.
"These nutrients might not make diabetes go away, but they might help you control your diabetes better, and that wouldn't come out in this study," he said.
Despite this, nutrition experts agreed that healthful food, rather than vitamin supplements, remains the best source of antioxidants for most people.
"I think the take-home message from this [review] is that there is no substitution for a well-balanced diet that includes plenty of fruits and vegetables," said Laurie Tansman, a nutritionist at the Mount Sinai School of Medicine in New York.
Ayoob agreed. "As soon as we get a study suggesting that people are healthier on vitamins, we get one that says 'no.'"
"You cannot get in a vitamin pill what you can get in a healthy diet," he said. "So the take-home point for consumers is that it's time to eat your fruits and veggies, because we do know the benefits of that with overwhelming evidence."