Relationship Of Percent Body Fat And Percent Trunk Fat With Bone Mineral Density Among Chinese, Black And White Subjects

Objective:The present study was designed to examine the relationship of %BF and percent trunk fat (%TF) with BMD. We are particularly interested to learn whether ethnic differences in %BF and %TF may influence BMD among Chinese, black and white subjects.Methods 1126 subjects aged≥18 years (805 Chinese,177 whites and 144 blacks) were evaluated. Percent body fat (%BF), percent trunk fat (%TF), and total and regional BMD including head, arm, leg, trunk, rib, spine and pelvis were measured by dual-energy X-ray absorptiometry. Linear regression models were developed to test the association of ethnicity,%BF, and interaction between ethnicity and %BF with BMD. The models were repeated again replacing %BF with %TF.Results Chinese subjects showed lower BMD in total and most regions compared to black and white subjects; however, these differences were eliminated between Chinese and whites within both sexes and between Chinese and black men when age, weight, height and %BF were added.%BF and %TF were negatively associated with most body regional BMD. The interactions between %BF,%TF and ethnicity were found in most body regional BMD among Chinese, white and black subjects for both men and women.Conclusion Both %BF and %TF have negative associations with BMD. With greater accumulation of% BF and %TF, both white and black subjects may experience a higher risk of low BMD than Chinese.