What This Means
This research suggests that differences between men and women in the types and amounts of bacteria living in the gut — and the chemical compounds those bacteria produce — may help explain why men and women develop heart disease, diabetes, and liver disease at different rates and different times in life. Women tend to be somewhat protected from these diseases during their reproductive years, but their risk rises substantially after menopause. The gut microbiome and its related metabolites, shaped in part by sex hormones like estrogen and testosterone, appear to influence key biological processes such as inflammation, blood sugar control, fat metabolism, and blood vessel function in ways that differ between sexes.
The review highlights specific bacteria (such as Akkermansia muciniphila, Eubacterium, and Ruminococcus) and metabolites (such as short-chain fatty acids, secondary bile acids, and TMAO) that show different patterns in men versus women and that are connected to cardiometabolic health. Sex hormones appear to be the primary driver of these differences, though the immune system and environmental factors also play a role. The authors note that findings across existing studies are inconsistent and that the biological mechanisms are not yet fully understood.
This research suggests that developing treatments or preventive strategies targeting the gut microbiome will likely need to account for a person's sex and hormonal status to be effective. The authors call for large, long-term studies that track gut bacteria, metabolites, and hormone levels together over time — especially across major hormonal transitions like puberty and menopause — to better understand these relationships and eventually develop sex-specific interventions for cardiometabolic disease.