WASHINGTON – Vitamin supplements can be a healthy addition to a nutritional diet, but experts say they can sometimes do more harm than good.

Numerous studies cited by The New York Times show that vitamins A, C, E and Beta-carotene can potentially increase a person’s risk of developing certain cancers.

“When someone is healthy, then taking supplements isn’t necessarily needed,” says Joy DuBost, a registered dietitian with the Academy of Nutrition and Dietetics. “When it comes to antioxidants, if you take in too much, it can almost have a counterproductive effect.”

Free radicals can be harmful, but according to researchers, consuming an excess number of antioxidants can also alter the body’s natural defenses.

“There’s a balance that’s needed between antioxidants and free radicals,” DuPost says.

According to DuPost, the best course of action is to layer a diet with nutrient- rich foods, including fruits, vegetables, whole grains, low-fat dairy and lean protein.

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