Objective: The relationship between fat accumulation in visceral or subcutaneous tissue and bone mineral density (BMD) remains unclear. In this study, we aim to shed light on this relationship by examining a large, nationally representative population. Methods: A weighted multiple linear regression model was established to evaluate the relationship between visceral fat, subcutaneous fat and BMD. Additionally, the potential nonlinear relationship was explored using smooth curve fitting method. Results: A total of 10455 participants between the ages of 20 and 59 were included in this study. Various weighted multiple linear regression models revealed a negative correlation between lumbar BMD T-score and visceral mass index (VMI) and subcutaneous mass index (SMI). However, the association between VMI and lumbar BMD T-score was U-shaped when we did smooth curve fitting, and the inflection point of 0.304kg/m² was determined using a two-stage linear regression model. Conclusions: Subcutaneous fat and BMD T-score were found to have a negative association, and visceral fat and BMD T-score were discovered to have a U-shaped connection. It is the significance of taking body composition and weight control into account while treating and preventing osteoporosis.
