Intersectional analysis of 4,591 US women from NHANES data reveals that combined social identities explain 13.8% of BMI variance and 4.6% of physical activity differences. Asian and Black women, those aged 35-49, foreign-born individuals, and women without high school diplomas showed lowest physical activity levels, while Black and Hispanic women under 64 had highest BMI scores. Race/ethnicity, age, education, nativity, and work status collectively accounted for over 97% of observed inequities. This intersectional approach moves beyond single-factor analyses to capture how multiple social identities compound health disparities. The findings illuminate targetable intervention points for addressing cardiovascular risk factors in vulnerable populations. However, the relatively modest variance explained suggests additional unmeasured factors significantly influence these health behaviors. The observational design limits causal inference, and this preprint awaits peer review which may refine these conclusions. While confirming known disparities, the quantification of intersectional effects provides a more nuanced framework for designing tailored health interventions that acknowledge women's complex social identities rather than treating demographic factors in isolation.