Antioxidants do not help in lowering heart disease - Study

People generally take vitamin supplements in the belief that this will improve their nutrition, skin health and wellbeing. They also take antioxidant pills to prevent heart disease. However, a new study has found that antioxidant supplements such as vitamins C, E and beta-carotene do not reduce the risk of heart disease in women most at risk.

The study, published in the August 13/27 issue of Archives of Internal Medicine, one of the JAMA/Archives journals, said that Vitamins C and E and beta carotene, which can be converted to vitamin A, do not appear to reduce the risk of cardiovascular events or death among women at high risk for heart disease.

To reach their findings, Dr. JoAnn E. Manson, the study's principal investigator and chief of preventive medicine at Brigham and Women's Hospital, in Boston and colleagues studied 8,171 women averaged 60.6 years old for 9.4 years.

The researchers divided the women, who all had existing heart disease, or at least three risk factors, such as diabetes, for developing it in the future, in three different groups.

And, then they randomly assigned them to take 500 milligrams of ascorbic acid (vitamin C) or a placebo every day; 600 international units of vitamin E or a placebo every other day; and 50 milligrams of beta carotene or a placebo every other day.

The randomized, double-blind, placebo-controlled study looked at the efficacy of all three vitamin supplements individually, as well as at doses above the recommended daily allowance in two- and three-way combinations.

During the study, of the total 1,450 study participants had one or more heart problems, including 274 heart attacks, 298 strokes, 889 bypass surgery or angioplasty and 395 cardiovascular deaths.

“I think we can close the book on this being a magic bullet for preventing cardiovascular disease,” said Manson. “Widespread use of antioxidant vitamin pills for cardiovascular disease prevention is not warranted.”

"There was no overall effect of ascorbic acid (vitamin C), vitamin E or beta carotene on the primary combined end point or on the individual secondary outcomes of myocardial infarction, stroke, coronary revascularization or cardiovascular disease death," said co-researcher Nancy R. Cook, Sc. D., of Brigham and Women's Hospital and Harvard Medical School.

However, the researchers said they witnessed fewer strokes risks in women who took active ascorbic acid and vitamin E, but said thorough study is needed.

An analysis of previous studies suggests that the antioxidant supplements beta carotene, vitamin A and vitamin E may reduce risk of cardiovascular disease. Vitamin D is naturally produced by skin in response to sunlight. Vitamin E is an antioxidant that helps reduce the damage caused by free radicals and unstable oxygen molecules generated by normal metabolism. Green leafy vegetables are rich source of Vitamin E.

Supported by the U.S. National Heart Lung and Blood Institute in Bethesda, Maryland, the latest study emphasized that people should get the vitamins from the fruits, vegetables-rich diet.

“Diets high in fruit and vegetable intake, and thus rich in such antioxidants, have been associated with reduced rates of coronary heart disease and stroke,” the study said. “Vitamins C and E and beta carotene are potential mediators of the apparent protective effect of a plant-based diet on cardiovascular disease.”