A cohort study of dietary fibre intake and menarche.

OBJECTIVE To evaluate the influence of dietary fibre on menarche in a cohort of pre-menarcheal girls. DESIGN Prospective cohort study. SETTING Ontario, Canada. SUBJECTS Free-living pre-menarcheal girls (n = 637), 6 to 14 years of age. METHODOLOGY Information on dietary intake, physical activity and date of menarche was collected at baseline and was updated annually by self-administered questionnaires for three years. Cox proportional hazards models were used to evaluate the association between dietary fibre and menarche, adjusting for age at entry to the study and potential confounders. RESULTS A higher intake of energy-adjusted dietary fibre was associated with a lower risk of (i.e. a later age at) menarche (relative hazard 0.54, 95% confidence interval (CI) 0.31-0.94 for highest vs. lowest quartile, P for trend = 0.027). At the fibre component level, a higher intake of energy-adjusted cellulose was associated with a lower risk of menarche (relative hazard 0.45, 95% CI 0.26-0.76, P for trend = 0.009). CONCLUSIONS The findings are consistent with the hypothesis that pre-menarcheal dietary intake can influence menarche.