title: Associations of menstrual cycle length with intake of soy, fat, and dietary fiber in Japanese women.
abstract: A decreased risk of breast cancer has been reported among women who have longer menstrual cycles or anovulatory cycles. The present study examined the relationships between intake of fat, soy, and dietary fiber and length of menstrual cycle among 341 Japanese women aged 18 to 29 yr old at two colleges and three nursing schools. Intake of nutrients and foods including fats, dietary fiber, and soy products was estimated through the use of a validated semi-quantitative food frequency questionnaire. The mean cycle length was determined for each women based on a prospective record of menstruation. Polyunsaturated fat intake was significantly inversely associated with cycle length; the means of cycle length were 33.2 and 31.0 days for the lowest and the highest quintiles of intake, respectively, after controlling for covariates (trend = 0.03). The odds ratio of a long cycle (> 35 days) for the highest vs. lowest quintile of dietary fiber intake was 2.12 (95% confidence interval 1.00-4.47), although the trend was not statistically significant. The data suggest that polyunsaturated fat and dietary fiber intake are associated with the parameters of menstrual cycle length, but further studies are required to better characterize these associations.
authors.affiliation: Department of Epidemiology and Preventive Medicine, University Graduate School of Medicine, Gifu, Japan. chisato@cc.gifu-u.ac.jp
authors.forename: Chisato
authors.initials: C
authors.lastname: Nagata
authors.forename: Shino
authors.initials: S
authors.lastname: Oba
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shimizu
mesh_terms: D000293:Adolescent; D000328:Adult; D001943:Breast Neoplasms / Q000453:epidemiology*; D016001:Confidence Intervals; D004034:Diet Surveys; D004041:Dietary Fats / Q000008:administration & dosage*; D004043:Dietary Fiber / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008597:Menstrual Cycle / Q000502:physiology*; D016017:Odds Ratio; D012307:Risk Factors; D045730:Soy Foods; D011795:Surveys and Questionnaires; D013997:Time Factors
chemical_list: D004041:Dietary Fats; D004043:Dietary Fiber