Calcium Intake and Bone Mineral Acquisition during the Pubertal Growth Spurt: Three-Year Follow-Up of the Kitakata Kids Health Study in Japan

Calcium intake during a growth spurt may influence bone mineral acquisition. However, no population-based cohort studies have examined the relationship between calcium intake and whole-body bone mineral acquisition in Japanese children. The present study investigated the relationship between calcium intake and whole-body bone mineral acquisition in community-dwelling children in a northeast region of Japan using dual-energy X-ray absorptiometry. The source population for the baseline survey comprised all school children in 4th through 6th grades (275 children; age range, 10-12 y) in the Shiokawa area of Kitakata City, Fukushima. We obtained complete information from 220 children (100 girls and 120 boys), and analyzed total body less head (TBLH) bone mineral content (BMC), TBLH areal bone mineral density (aBMD), and bone mineral apparent density (BMAD) as an estimate of volumetric bone density. The Food Frequency Questionnaire for the Prevention and Management of Osteoporosis was validated in a previous study and used to estimate dietary nutrient intake. At baseline, mean calcium intake was 641 mg/d in girls and 660 mg/d in boys. Calcium intake in boys showed a significant (p<0.05) relationship with TBLH BMC and TBLH aBMD at follow-up, and with changes in TBLH BMC, TBLH aBMD, and TB BMAD from baseline to follow-up. After adjusting for potential confounding factors including body weight, we found no significant relationships between calcium intake and bone mineral parameters. Further studies are needed to clarify whether calcium intake affects bone mineral acquisition during pubertal growth spurts in the Japanese population.