Antioxidants May Not Reduce Heart Risk in Smokers
06/06/00
NEW YORK (Reuters Health) - Antioxidants are unlikely to do much to help smokers avoid cardiac disease, new study findings suggest.
While vitamins C and E have been touted as antioxidants that may reduce atherosclerosis (the build-up of plaque in the arteries), investigators have found they actually do very little to combat the detrimental effects of smoking. The report is published in the June issue of the Journal of the American College of Nutrition.
``Just quit smoking,'' advised Dr. Cindy Fuller from the University of North Carolina at Greensboro, lead author of the study.
Smokers are at high risk for premature heart disease because the release of free radicals while smoking is associated with the oxidization of LDL (low-density lipoprotein) cholesterol. This ``bad'' cholesterol leads to hardening of the arteries.
Some previous research had shown that taking antioxidants could reduce this effect. One test by Fuller and colleagues showed that vitamin E had a small beneficial effect, but vitamin C did not alter the LDL at all, Fuller said. Two other tests found neither vitamin made a difference.
Thirty short-term smokers (half a pack of day for less than 5 years) were enrolled in the study. All were students around 20 years of age. For 8 weeks, the participants were asked to continue smoking and were randomly assigned to one of the following daily regimens: 1 gram of vitamin C; 400 international units of vitamin E; both vitamins; or a placebo--a ``dummy'' pill used for comparison purposes.
The LDL of subjects who took vitamin E took longer to oxidize when copper was added to the test tube, indicating some protective effect, Fuller told Reuters Health. ``However, we didn't see anything with the vitamin C group.''
Two separate tests by the researchers to measure oxidation of white blood cells, a more specific test thought to reflect what is happening in the body, did not indicate any positive changes from the intake of antioxidants.
``Based on the results of this small study, the only way for young smokers to reduce oxidative damage to the vasculature by tobacco is to quit smoking rather than to take antioxidant vitamin supplements,'' the researchers write.
While Fuller was surprised by the results of this study, she was somewhat pleased to learn that the antioxidants could not be seen as a panacea for problems that may result from smoking. ``I had a philosophical problem with recommending supplements on a blanket basis. Smokers would take that as a license to continue smoking.''