To investigate the claim that vitamin E can affect human sexual functioning, 1000-IU vitamin E capsules (alpha-tocopherol) were administered daily for 28 days in a double-blind placebo study. Thirty-five subjects in this pilot study reported daily responses to questionnaires on sexual arousal and behavior. No differences in sexual arousal or behavior were found between the two groups. The one significant difference was that the vitamin E subjects were more likely than the placebo subjects to report either positive or negative nonsexual effects.