Bone mineral content and anthropometric variables in men: a cross-sectional study in 324 normal subjects

Total body bone mineral content (TBBMC), total body bone mineral density (TBBMD), and regional bone mineral content (BMC) were determined with dual energy X-ray absorptiometry and correlated with different anthropometric variables in 324 normal male subjects aged 15 to 85 years, in order to obtain further knowledge of the controversial course of bone mass in males. These subjects showed increased TBBMC and TBBMD up to the age of 25-29 years. A positive and significant (p < 0.001) correlation was observed between TBBMC and TBBMD and with BMC with age (p < 0.001), as well as between age and body weight (p < 0.001) and between the latter and body fat (p < 0.001). Age did not correlate with weight or TBBMC, TBBMD, and regional BMC in subjects older than 29 years, while a significant and positive correlation between body weight and muscle mass was observed with bone mass (p < 0.001). By multiple regression analysis, TBBMC was significantly independent of fat-free mass (FFM) and lean body mass (LBM) (p < 0.01). These findings led us to point out that bone mass increases until the age of 29 years and that changes depend more on weight that on age in men. The rate of bone mass loss with age was 0.23%, that of soft tissue 0.35%, while fat mass increased 0.7% per year.