Cardiovascular disease (CVD) and dementia are leading causes of death in women, with dementia disproportionately affecting females. Both share risk factors such as type 2 and gestational diabetes. While diabetes and CVD risk factors are well studied, gaps remain in understanding dementia’s lifespan influences, sex-specific effects, and social determinants. This report advocates a convergence science approach, integrating basic, behavioral, and implementation sciences, to address these gaps. We propose a novel framework to examine shared cardiometabolic risks across the lifespan, enabling targeted early interventions to reduce dementia burden and improve heart-brain health outcomes in women.