Bone mass of overweight affluent Indian youth and its sex-specific association with body composition

Abstract

SUMMARY: The study assessed whether overweight is associated with better bone densities in healthy youth. It was observed that overweight individuals had better BMDs at the hip but not at other sites after controlling for the bone area. Lean body mass was an important determinant of BMDs in men, but both lean and fat mass were important for BMDs in women. INTRODUCTION: The study assessed the relationship of overweight and obesity to the bone mass in young men and women consuming adequate calcium. METHODS: Bone and body composition parameters were measured using dual energy X-ray absorptiometry in overweight men (n = 74) and women (n = 77) in the age group of 20-35 years and compared with controls having normal body mass index (BMI). Biochemical parameters of bone metabolism were also assessed. RESULTS: After adjustment for whole body bone area, bone mineral densities (BMDs) at femoral neck and hip were significantly higher in overweight individuals when compared with controls. However, BMD at lumbar spine, forearm, and whole body were not significantly different in the two BMI groups. Overweight women had lower vitamin D and higher parathormone levels than controls. Regression analyses indicated that height was an important determinant of BMD at most of the skeletal sites in both men and women. Lean body mass was an important determinant of BMDs in men, but both lean and fat mass were important for BMDs in women. CONCLUSION: Overweight may be associated with better BMDs at the hip but not at other sites after controlling for the bone area. Body composition parameters may have sex-specific associations with BMD.

Fig. 1

Bone mineral densities at different skeletal sites in the two BMI groups of men. There were significant differences in the BMD in the two BMI groups of men at femoral neck (p = 0.006), hip (p = 0.008), and lumbar spine (p = 0.043)

Fig. 2

Bone mineral densities at different skeletal sites in the two BMI groups of women. There were significant differences in the BMD of the two BMI groups of women at femoral neck (p < 0.001), hip (p < 0.001), lumbar spine (p = 0.018), and forearm (p = 0.001)