Passive smoking is considered causally associated with lung cancer and ischemic heart disease. Smokers and those who live in the same household have worse diets than nonsmokers, consuming fewer servings of fruits and vegetables which are rich sources of micronutrients. Alberg et al. studied the serum micronutrient levels of subjects, usually spouses, who were living with active smokers. Among these non- and former smokers, exposure to passive smoke was associated with low serum concentrations of the same carotenoids that are depleted by active smoking. Though the data were conclusive in demonstrating that the passive smokers were nutrient-depleted, further studies which additionally assess dietary intake of the subjects will be needed to determine whether depletion of antioxidants is due to smoke exposure, shared inadequate diets, or both.
The study population of 1590 individuals were equally divided between men and women, averaged 54 years of age, and were nearly all Caucasian. Results of serum analyses for micronutrient levels were correlated with census data on a number of lifestyle factors, including smoking status. Eighty-four percent of the subjects exposed to passive smoke had a spouse who smoked. Never and former smokers had consistently lower serum concentrations of total carotenoids, b-carotene, a-carotene, and cryptoxanthin than did those not exposed to smoking at home. The strikingly similar profiles between active and passive smokers with respect to their relative carotenoid deficiencies points to cigarette smoke exposure as a possible cause of the subjects’ low micronutrient levels.
An accompanying editorial by Albert van der Vliet emphasizes that the development of carcinogenesis and atherosclerosis follows a very complex multistage course, involving inflammatory-immune processes and genetic factors in addition to the influence of antioxidant micronutrients such as b-carotene. He recommends against supplementation with b-carotene for those exposed to passive smoke because several recent trials have been unsuccessful, and because recent studies have indicated that although b-carotene itself has anticarcinogenic characteristics, it can form carotenoid metabolites with procarcinogenic properties, especially in response to cigarette smoke-induced stress.
Alberg, Anthony et al. Household exposure to passive cigarette smoking and serum micronutrient concentrations. Am J Clin Nutr 2000;72:1576-82.
Van der Vliet, Albert. Cigarettes, cancer, and carotenoids: a continuing, unresolved antioxidant paradox. Am J Clin Nutr 2000;72:1421-3.
This media release is provided by The American Society for Clinical Nutrition, to provide current information on nutrition-related research. This information should not be construed as medical advice. If you have a medical concern, consult your doctor. To see the complete text of this article, please go to: http://www.faseb.org/ajcn/December/(11578)-Alberg.PDF or http://www.faseb.org/ajcn/December/(12249)-vanderVl.PDF
For more information please contact: aalberg@jhsph.edu or avandervliet@ucdavis.edu
Journal
American Journal of Clinical Nutrition