Use of smokeless tobacco and cigarettes--effects on plasma levels of antioxidant vitamins.

In a population-based sample of 40-49-year-old men, plasma levels of antioxidant vitamins were measured in 17 regular users of smokeless tobacco (oral snuff), 26 regular smokers and 54 non-tobacco users. Vitamin intake by tobacco use was assessed by a food frequency questionnaire in 174 men in the 40-49 year age range. Compared with non-tobacco users, snuff dippers had similar plasma levels of ascorbate, tocopherols and carotenoids, whereas these were all significantly reduced in smokers. Smokers, but not snuff dippers, had plasma levels of ascorbate significantly below those expected from ascorbic acid intake, indicating enhanced expenditure of ascorbate in smokers but not in snuff dippers. The results show that plasma levels of antioxidant vitamins are not reduced in snuff dippers as they are in smokers, possibly as the combined result of higher intake and lower expenditure of ascorbate and tocopherols in those who use smokeless tobacco.