Dietary Patterns and the Risk of Composite-Defined Osteoporosis in Pre- and Postmenopausal Women: A Prospective Cohort Study.

Background/Objectives: This study aimed to investigate the association between dietary patterns and the risk of developing osteoporosis in women, emphasizing the role of nutrition in bone health during menopause-related hormonal changes. Methods: We conducted a prospective study involving 4865 women aged 40-69 years without osteoporosis at baseline. Dietary information was collected using a validated semi-quantitative food frequency questionnaire, and composite-defined osteoporosis (CDO) was defined using self-administered questionnaires and quantitative ultrasound. Multivariate Cox proportional hazards regression analysis was employed to calculate hazard ratios and 95% confidence intervals to assess the association between dietary patterns and the risk of CDO. Results: During a median follow-up of 8.26 years, 895 and 1525 cases of CDO were reported in premenopausal and postmenopausal women, respectively. Three dietary patterns were identified in premenopausal women: the "Vegetables and Seafood," "Western," and "White rice, Meat, and Alcohol" patterns. In postmenopausal women, the "Diverse," "Plant-based," and "Sweets and Drinks" patterns were identified. Among premenopausal women, the "White rice, Meat, and Alcohol" pattern was associated with a significantly greater risk of CDO in the highest tertile compared with that in the lowest tertile, whereas no significant patterns were observed in postmenopausal women. Conclusions: These findings underscore the importance of dietary factors in maintaining bone health, particularly in premenopausal women. Encouraging the reduction in dietary factors associated with an increased osteoporosis risk may help improve bone health and quality of life in women, especially before significant menopause-induced bone loss occurs. This study highlights the need for early dietary interventions to prevent osteoporosis in women.