Despite some reports that antioxidant vitamins have cardiovascular benefits, a panel of experts at the American Heart Association (AHA) has concluded that there is too little evidence to recommend taking antioxidant supplements to reduce the risk of heart disease.

Instead the AHA panel advises the public to get plenty of antioxidants from food sources, such as fruits, vegetables, whole grains and nuts.

“We know that diets high in fruits and vegetables are associated with decreased risk of cardiovascular disease,” lead panel Dr. Penny M. Kris-Etherton of Pennsylvania State University said in a press release. “Thus, following a diet consistent with the American Heart Association’s dietary guidelines is recommended.”

The Dallas-based group advises eating five or more servings of fruits and vegetables each day and at least six servings of grain products, including whole grain foods.

Antioxidants, including vitamins C and E and beta-carotene, target a process called oxidation in which cell-damaging substances called free radicals accumulate. Oxidation is suspected of increasing the risk of several diseases, including heart disease.

There is some evidence that oxidation plays a role in the development of deposits called plaques that build up in diseased arteries. What’s more, some population-based studies have observed lower rates of heart disease in people who take antioxidant supplements, such as vitamin E.

In 1999, the AHA began advising the public to consume foods that are rich in antioxidants, but concluded that there was not enough evidence to recommend the use of antioxidant supplements.

During the past 5 years, several clinical trials have investigated the effect of antioxidant supplements on heart disease, and a panel of AHA experts reviewed the results to see whether it was time to start recommending antioxidant supplements.

Most studies have not demonstrated that antioxidant supplements have cardiovascular benefits, the panel reports in the August 3rd issue of Circulation: Journal of the American Heart Association.

In fact, a few studies found that antioxidant supplements may have a detrimental effect on cardiovascular risk.

But the apparent lack of an effect of antioxidant supplements in recent clinical trials doesn’t mean that oxidation doesn’t play a role in the development of artery disease, according to the panel.

“While the research shows that antioxidant supplements have no benefit, the role oxidative stress plays in the development and progression of heart disease has yet to be clarified,” Kris-Etherton said.

SOURCE: Circulation, August 3, 2004.