No protective effect on cancer from long-term vitamin E or vitamin C supplementation

Nov 16, 2008

The Physicians' Health Study II is a large-scale, long-term, randomized clinical trial that included 14,641 physicians who were at least 50 years old at enrollment. These physicians were given 400 IU of vitamin E every other day or its placebo, or 500 mg of vitamin C daily or its placebo.

Researchers followed these patients for up to 10 years for the development of cancer with high rates of completion of annual questionnaires, and the confirmation of reported cancer endpoints.

Analyses indicate that randomization to vitamin E did not have a significant effect on prostate cancer. This lack of effect for vitamin E also extended to total cancer. Vitamin C had a similar lack of effect on total cancer.

"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, Sc.D., M.P.H., 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.

Previous laboratory research and observational studies in which people who reported eating a diet rich in vitamins E and C were found to have a lower risk of cancer, had suggested that taking these vitamins as individual supplements may offer some protective benefits.

Study co-author and principal investigator J. Michael Gaziano, M.D., M.P.H., associate professor of medicine at Brigham and Women's Hospital and VA Boston, adds, "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."

Finally, Sesso said that these results provide clinically meaningful new information. "Our results represent one of only a few clinical trials that have tested this idea. The final component of the Physicians' Health Study II, testing daily multivitamin supplementation, remains ongoing."

Source: American Association for Cancer Research

Explore further: Study finds new potential melanoma drug target

Related Stories

Research prompts rethink of enzyme evolution

7 hours ago

New research by scientists at New Zealand's University of Otago suggests a need for a fundamental rethink of the evolutionary path of enzymes, the proteins vital to all life on Earth.

Elderly crickets are set in their ways, study finds

7 hours ago

As insects grow old their behaviour becomes increasingly predictable according to new research published in the journal Behavioural Ecology. The study, which set out to understand how personality alters with a ...

Recommended for you

Study finds new potential melanoma drug target

May 02, 2015

A new treatment for melanoma could be on the horizon, thanks to a finding by a UNC Lineberger Comprehensive Cancer Center-led team. In the study, which was published online today in the journal Clinical Ca ...

Surgery for terminal cancer patients still common

May 02, 2015

The number of surgeries performed on terminally ill cancer patients has not dropped in recent years, despite more attention to the importance of less invasive care for these patients to relieve symptoms and ...

Study provides comprehensive look at brain cancer treatments

May 01, 2015

Led by the Translational Genomics Research Institute (TGen) and UC San Francisco (UCSF), a comprehensive genetic review of treatment strategies for glioblastoma brain tumors was published today in the Oxford University Press ...

How artificial tanning can lead to melanoma

May 01, 2015

Young women may be up on the latest fashions and trends as they prepare for prom season. But what many don't know is that the tan that looks oh-so-good with their dress may be the first step toward skin cancer.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.