Although touting the health benefits of antioxidant-rich foods are ubiquitous, researchers have found that the highly praised substances may do more harm than good in patients with certain types of cancer, The Washington Post reported.

Researchers from Sweden's University of Gothenburg found that supplements of antioxidants such as vitamin E and beta carotene may accelerate the growth of early lung tumors in high-risk populations such as smokers, rather than protect them from cancer, The Washington Post reported.

Antioxidants are chemical compounds that prevent or delay cell damage.

For the study, scientists gave vitamin E supplements and a generic drug called N-acetylcysteine, both antioxidants, to mice with early lung cancer. They found that the supplements sped the growth of the mice's tumors and made them die faster than mice who didn't take the supplements.

"Antioxidants caused a three-fold increase in the number of tumors and also tumor aggressiveness, and the antioxidants caused the mice to die twice as fast," said study author Martin Bergo of the University of Gothenburg in Sweden. "If we gave a low dose, tumors increased a little bit. And if we gave a high dose, tumors increased a lot."

Per Lindahl, biologist at Sweden's University of Gothenburg and a co-author of the study, told reporters antioxidants "allow cancer cells to escape cells' own defense system," which lets existing tumors proliferates uncontrollably.

Researchers said more studies need to be done in humans before issuing general recommendations about the use of antioxidant supplements, The Washington Post reported.

"We need to understand if this is limited to lung cancer . . . or if the antioxidants can accelerate the growth of other tumors such as malignant melanoma, leukemia, G.I. tumors. We don't know anything about this. It is possible that antioxidants will increase the growth of some of the cancers, and it is possible that it will prevent others," Bergo said.

The study was published in the journal Science Translational Medicine.