Effect of weight and body mass index on bone mineral density in healthy postmenopausal women

Objective To investigate the effect of weight and body mass index (BMI) on bone mineral density (BMD) in healthy postmenopausal women. Methods BMD at various skeletal sites was measured by dual energy X-ray absorptiometry in 591 healthy postmenopausal women, and all women were divided into low BMI, normal BMI and obese groups according to their BMI.Results BMD increased with BMI increasing (P0.01). BMD decreased with the age increasing (P0.01). The BMD at various sites in obese group was higher than those in normal BMI group and low BMI group (P0.05 or P0.01). Both age and weight were important factors affecting BMD. A negative correlation was found between age and BMD, while a positive correlation was found between weight and BMD. A positive correlation was found between menopausal age and BMD in the anterior spine, and there was no correlation between BMI and BMD.Conclusions Weight is one of most important factors affecting BMD. The women with low BMI should be measured BMD on schedule for intervening earlier.