Caffeine-containing beverages and premenstrual syndrome in young women.

I evaluated the hypothesis that consumption of caffeine-containing beverages causes premenstrual syndrome by studying 295 college sophomores. Data about premenstrual syndrome and beverage consumption were collected by a self-administered questionnaire. Analysis of the data revealed that consumption of caffeine-containing beverages is strongly related to the presence and severity of premenstrual syndrome and that the effects exist for most of the premenstrual symptoms studied.