(China Daily- Agencies)
Updated: 2008-03-01 09:55

WASHINGTON -- If you thought taking vitamin supplements would reduce the risk of lung cancer, think again, for vitamin E supplements can actually raise the risk.

Researchers who studied 77,721 people, aged between 50 and 76, in Washington state over the past decade, said on Friday that people who took high doses of vitamin E, especially smokers, had a small but statistically significant elevated risk of developing lung cancer.

They tracked the subjects' use of supplemental multi-vitamins, vitamin C, vitamin E and folate to see if it offered protection from lung cancer. But they found that none of the vitamins looked at in the study was tied to a reduced risk.

"If you could find some sort of magic pill - a pill you could take once a day to decrease your risk - that would be ideal. But we obviously, unfortunately, didn't find that in our study," lead researcher Christopher Slatore, of the University of Washington in Seattle, said.

The subjects of the study were followed for four years, and 521 developed lung cancer, the vast majority of them smokers or former smokers, Slatore's team reported in the American Journal of Respiratory and Critical Care Medicine.

"Some estimates are that around 50 percent of the American public takes supplemental vitamins of some sort. There's been a lot of thought about: 'do these supplements actually prevent chronic diseases like lung cancer, other cancers, heart disease'?" Slatore said.

The research did not look at beta-carotene, but previous work showed people taking beta-carotene supplements, especially smokers, had a higher risk of developing lung cancer than those who did not.

Among those in the study who developed lung cancer, the researchers saw a small increased risk associated with vitamin E supplements in addition to the expected links to smoking, family history and age.

This amounted to a 28 percent increased risk of developing lung cancer for those taking vitamin E supplements at a dose of 400 mg daily for 10 years, the researchers said.

"For folks - especially smokers - I would definitely recommend that they not take vitamin E (as a supplement) unless they have a very strong reason to take it," Slatore said.

The notion that vitamin supplements are healthful, or at least not harmful, arises from the desire of many people to match the benefits of a healthful diet with a convenient pill, Tim Byers, of the University of Colorado School of Medicine, wrote in an editorial accompanying the study.