Physical activity and mammographic density in an Asian multi-ethnic cohort

Background Physical activity is a modifiable lifestyle factor associated with reduced breast cancer risk. Mammographic density is a strong, independent risk factor for breast cancer, and some breast cancer risk factors have been shown to modify mammographic density. However, the effect of physical activity on mammographic density, studied predominantly among Caucasians, has yielded conflicting results. In this study, we examined, in an Asian population, the association between physical activity and mammographic density.