Diet, the Gut Microbiome, and Estrogen Physiology: A Review in Menopausal Health and Interventions

Menopause represents a key transitional phase in women's health, characterized by declining estrogen levels and increased risk for cardiometabolic, musculoskeletal, and urogenital disorders. Beyond its endocrine roots, emerging evidence highlights the gut microbiome as a critical modulator of systemic hormonal balance. This review synthesizes current understanding of the bidirectional relationship between estrogen and the gut microbiome and its implications for women's health during menopause. Evidence from current studies reveals distinct findings across populations, reflecting the complexity of estrogen regulation in part by the gut microbiome (i.e., estrobolome). While no ideal gut microbial composition has been identified for women across stages of perimenopause, likely due to geographically unique gut microbiome profiles among healthy women, greater microbial diversity has been positively associated with improved estrogen regulation. Conversely, reduced diversity and altered Firmicutes/Bacteroidetes ratios have been linked to biomarkers of inflammation during perimenopause, which is a key driver across many perimenopausal symptoms. Although hormone replacement therapy remains the primary clinical intervention during perimenopause, we highlight emerging evidence on the adjuvant potential of diet, synbiotics, phytoestrogens, and strain-specific probiotics in modulating the estrogen-gut microbiome axis for improved health span trajectories and better symptom management. Future longitudinal studies integrating diet, gut microbiome profiles and symptom trajectories are essential to clarify these mechanisms across ethnicity and geography. Ultimately, understanding localized diet-microbiome interactions will enable the development of accessible, personalized, and non-hormonal strategies to complement and increase agency in proactive management during the perimenopausal transition.