Recently many young women in Japan have been restricting their dietary intake for cosmetic purposes. In this study, the relation between diet and menstrual disorders was investigated by responses to a questionnaire. Subjects ranging from 18 to 20 years old were recruited from 716 female students at Ashiya College. Dietary habits were classified into group I (having no experience with dieting), group II (those currently on a diet) and group III (those with a history of dieting). The intensity of dysmenorrhea was classified into three grades. All participants were divided into two groups as having regular or irregular menstruation. The frequency of irregular menstruation in group II was higher than that in the other groups, while group III had higher intensity of dysmenorrhea than the other groups. These findings suggest that diet during adolescence has long-lasting adverse effects on reproductive function in young women.