Long-Term Use of Vitamins C, E Do Not Prevent Cancer, Study Concludes

Long-term use of Vitamins C and E does not prevent cancer, concluded the Physicians' Health Study II, the American Association for Cancer Research (Philadelphia) announced on November 16.

The study included 14,641 physicians, who were given either a placebo or 400 IU of vitamin E every other day; or 500 mg of vitamin C daily or its placebo.

Researchers followed these patients for up to 10 years.

"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," said Howard D. Sesso, MPH., an assistant professor of medicine at Brigham and Women's Hospital.

"While vitamin E and C supplement use did not produce any protective benefits, they also did not cause any harm," he added.

Study co-author J. Michael Gaziano, MD, associate professor of medicine at Brigham and Women's Hospital and VA Boston, said, "Individual vitamin supplements such as vitamin E and C do not appear to provide the same potential advantages as vitamins included as part of a healthy, balanced diet."

"Our results represent one of only a few clinical trials that have tested this idea,” Sesso said.

“The final component of the Physicians' Health Study II, testing daily multivitamin supplementation, remains ongoing."