Differences and Trends in Antioxidant Dietary Intake in Smokers and Non-smokers, 1980–1992: The Minnesota Heart Survey

Abstract

PURPOSE: Differences and secular trends in dietary antioxidant vitamin intake (vitamins E, C, and β-carotene) in current non-smokers, light smokers, and heavy smokers were examined as part of the Minnesota Heart Survey.METHODS: Three cross-sectional surveys were conducted in adults ages 25–74 years in 1980–82 N = 1682, 1985–87 N = 2326, and 1990–92 N = 2487. Dietary information was obtained from a 24-hour dietary recall. Smoking was assessed through self-report. Intakes were adjusted for age, energy intake, body mass index, education level, and exercise level (vitamins E, C and β-carotene).RESULTS: Antioxidant vitamin intakes were significantly higher in non-smokers than in light (1–20 cig/day) and heavy smokers (>20 cig/day) when all three survey periods were combined. In men, mean vitamin E intake was 9.2 mg, 8.6 mg, and 7.8 mg for non-smokers, light smokers, and heavy smokers, respectively. Results were similar in men for β-carotene (non-smokers 1408 μg, light smokers 1287 μg, and heavy smokers 1064 μg), and vitamin C (non-smokers 81 mg, light smokers 67 mg, and heavy smokers 56 mg). Women had results of similar magnitude and direction. From 1980–92, secular trends in men showed non-significant increases from 1980–82 to 1990–92 in β-carotene (+6.1%), while decreases were observed in vitamins E (−1.1%) and C (−2.6%). In contrast, women had large decreases in all antioxidant vitamin intakes: vitamin E (−13%), vitamin C (−18.6%), and β-carotene (−16.2%).CONCLUSIONS: Light and heavy smokers had a significantly lower overall mean dietary antioxidant vitamin intake than non-smokers. Over the decade, antioxidant dietary intake remained relatively stable in men and decreased in women in Minneapolis-St. Paul, despite improvements in access to antioxidant rich fruits and vegetables.