Bone mineral density, body composition and dietary intake in Asian Indian and Caucasian males

Background: The difference in osteoporotic fractures across different ethnic groups could be due to the differences in body composition and eating habits. The variation in areal bone mineral density (aBMD), body composition and dietary intake between immigrant Asian Indians and Caucasians are unknown. Objective: The objective of this study was to examine the differences in aBMD, body composition and dietary intake between immigrant Asian Indians and Caucasians matched for age and body mass index (BMI). Also, we examined the relationship between body composition and aBMD and how might the relationships differ between the two groups. Design: A convenient sample of 32 healthy males who self-identified themselves as either Asian Indians (n=16) or Caucasians (n=16) were recruited for this cross-sectional study. Dual-energy x-ray absorptiometry (DXA) was used for measuring aBMD and bone mineral content (BMC) at the lumbar spine, femoral neck, 33% radius of the non-dominant hand and whole body. Body composition was measured using whole body scan by DXA. Dietary intake was assessed using 24-hour food recall and food frequency questionnaires. Results: There was no difference between groups in age and BMI. Lean mass was lower in Asian Indians compared Caucasians (p=0.03). aBMD at measured sites were similar between two groups (all p>0.05). However, BMC was lower at all skeletal sites (all p<0.05). In all overall sample, lean mass correlated positively with aBMD at the lumbar spine (p<0.05), but with aBMD at the femoral neck in Caucasian males only (p=0.03). Fat mass did not correlate with aBMD at any sites (all p>0.05). There were no differences in the correlation between body composition with aBMD between Asian Indians and Caucasians. Regarding dietary intake, calcium and magnesium intakes were not different between the two ethnic groups (all p<0.05). Conclusion: Asian Indian men have lower lean mass and BMC at different skeletal sites, but similar other body composition variables and dietary intakes compared to age and BMI matched Caucasians. Lean mass showed a positive correlation with aBMD. Since the scope of this study was limited to examine the difference in bone density using aBMD, the study highlights the need for further research to examine the variability in bone turnover between immigrant Asian Indians and Caucasians to see if the findings from biochemical properties and bone density are similar.