A long-term study of more than 14,000 male physicians concluded that taking daily supplements of vitamin E or vitamin C did not prevent cardiovascular disease. A separate study involving 35,000 men found that taking vitamin E and vitamin C supplements did not decrease prostate cancer risk.

The National Cancer Institute decided to suspend a study on the benefits of vitamin E and selenium supplements treatments on prostate cancer prevention. The study, called SELECT (Selenium and Vitamin E Cancer Prevention Trial), found a higher risk for aggressive prostate cancer in participants taking only vitamin E and a small increased risk of developing diabetes in subjects taking only selenium. The findings of the study were a major disappointment to those that had hoped that these supplements might prove to be some powerful anti-cancer agents.

“I am afraid it will be the end of the story for large trials of vitamin E and selenium to prevent prostate cancer,” said the study investigator Edward M. Messing, professor and chairman of urology and deputy director of the Cancer Center at the University of Rochester.

For the second study, scientists enrolled 14,641 male physicians, dividing them into four groups. The first group took 400 international units of vitamin E every other day and 500 milligrams of vitamin C daily, the second group took vitamin E and a placebo vitamin C, participants in the third group were given vitamin C and placebo vitamin E and the last took only placebos.

After eight years, the rates of “major cardiovascular events”, such as heart attack, stroke, congestive heart failure or angina were similar among all four groups. Overall, there were 1,929 cases of cancer, including 1,013 cases of prostate cancer. 490 men taking vitamin E developed prostate cancer compared to 523 in the placebo group.

The results of the study, funded by the National Institutes of Health and several vitamin makers, were reported Sunday at an American Association for Cancer Research conference in Washington.

“After nearly 10 years of supplementation with either vitamin E or vitamin C, we found no evidence supporting the use of either supplement in the prevention of cancer,” Howard Sesso, an assistant professor at Birmingham and Women’s Hospital, says in a news release. “There are no compelling reasons to take either vitamin E or C for cardiovascular disease prevention,” Sesso said, adding that there was also no sign that either supplement was harmful. “We’re still testing whether taking a standard multivitamin has an effect.”

There are some other steps you can take to avoid heart disease: don’t smoke, get regular exercise and eat healthy foods. Studies have shown a healthy diet, with lots of whole grains, fruits, vegetables and nuts significantly reduces the risk of heart disease.

“The American Cancer Society recommends getting these and other nutrients by eating a mostly plant-based diet with a variety of vegetables, fruits and whole grains. A bonus is that this type of diet helps to prevent obesity, which increases the risk of several cancers,” said Marji McCullough, nutrition chief at the American Cancer Society.