Min KK, Hee Choi S, Lim S, Hoon Moon J, Hee KJ, Wan KS, Chul JH, Soo SC. - 45418 N - J Clin Endocrinol Metab 2014 ; : jc20141006.

Interactions between Dietary Calcium Intake and Bone Mineral Density or Bone Geometry in a Low Calcium Intake Population (KNHANES IV 2008-2010)

Context: Little is known about the interactions between dietary calcium intake and bone strength parameters in populations or areas with low calcium intake. Objective: To investigate the relationship between dietary calcium intake and bone mineral density (BMD) or bone geometry in an Asian population with low calcium intake Design and Setting: A cross-sectional study of data from the Korea National Health and Nutrition Examination Survey 2008-2010. Participants: A total of 3448 men and 3812 women over 50 years were stratified by daily dietary calcium intake: <400 mg/day, 400-799 mg/day, 800-1199 mg/day, and >/=1200 mg/day. Main Outcome Measures: BMD was measured by dual energy X-ray absorptiometry and the geometric index was calculated. Results: Mean daily calcium intake was 470 mg/day in this population. BMD in the lumbar spine (both sexes) and femoral neck (women) was significantly lower only when calcium intake was <400 mg/day. In men, femoral neck and total hip BMD was positively related to calcium intake up to 1200 mg/day. Calcium intake <400 mg/day was negatively related to femoral cortical thickness and buckling ratio. These interactions disappeared when the 25-hydroxyvitamin D level was >/=30 ng/mL in men and >/=20 ng/mL in women. Conclusions: Low calcium intake was significantly related with low BMD and increased risk of osteoporosis. However, the association between calcium and BMD was not consistently linear and a sufficient vitamin D level appears to compensate for the negative influences of low calcium intake on bone.