This 6-mo controlled dietary study compared the effect of 30 g alcohol/d for three menstrual cycles with three alcohol-free cycles on plasma carotenoid concentrations in 18 nonsmoking, premenopausal women. Participants were randomly allocated within a crossover design to either phase and consumed approximately 6 mg total carotenoids/d under isoenergetic conditions. Blood was drawn during the third menstrual cycle of each alcohol phase. After adjustment for the mean daily specific carotenoid and energy intakes for each alcohol phase, the paired differences in mean plasma alpha- and beta-carotene concentrations were significantly higher by 19% (P = 0.027) and 13% (P = 0.034), respectively, during the alcohol-intake phase of the study. The paired difference in mean plasma lutein/zeaxanthin concentration was significantly lower by 17% (P = 0.031) when the participants consumed alcohol than when they did not. This is the first reported study in women to document the independent effect of alcohol on plasma carotenoid concentrations without the potential interaction of smoking under controlled dietary conditions.