Importance of fat mass and lean mass on bone health in men: the Fourth Korean National Health and Nutrition Examination Survey (KNHANES IV)

Summary

This study was aimed to evaluate the association between body composition and bone health. High lean mass and low fat mass have protective effects on bone health in men representative of the national population.

Introduction

The aim of this study was to evaluate the association between body composition (fat mass and lean mass) and bone health in men.

Methods

Totally, 3,945 men (age ≥20 years) from the fourth Korean National Health and Nutrition Examination Survey of 2008–2009 (KNHANES IV) were included in this study. Body composition and bone mineral densities (BMDs) were measured using dual energy X-ray absorptiometry. Osteopenia or osteoporosis was identified on the basis of the World Health Organization T-score criteria.

Results

Multiple linear regression analyses showed that BMDs of the whole body, femoral neck, and lumbar spine were positively associated with lean mass and negatively associated with fat mass, after controlling for body weight and other potential confounders. Subjects with more fat mass or less lean mass, categorized according to quartiles of fat mass and lean mass, had higher odds of having osteopenia or osteoporosis, as shown by multivariable logistic regression (P for trend <0.001).

Conclusions

High lean mass and low fat mass have protective effects on bone health in a population of Korean adult men. Fat mass appears to exert a detrimental effect on BMD, in contrast with the positive weight-bearing effect. Body composition seems to be a more important determinant for bone health than simple body weight.