Bone Mineral Density of Adolescents as Affected by Calcium Intake through Milk and Milk Products

• Published in: International dairy journal 1998-01, Vol.8 (9), p.759-764
• Main Authors: Renner, E., Hermes, M., Stracke, H.
• Format: Article
• Language: English
• Subjects: adolescents; Biological and medical sciences; bone mineral content; bone mineral density; calcium intake; dietary intervention; Fundamental and applied biological sciences. Psychology; milk and dairy products; prophylaxis to osteoporosis; Skeleton and joints; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 0958-6946; 1879-0143
• DOI: 10.1016/S0958-6946(98)00120-4

Elevated levels of milk and milk products were incorporated into the diet of 15–16 yr old adolescents with subaverage bone mineral density in order to obtain a daily calcium intake of about 1200 mg. The bone mineral density was significantly improved by about 50% when compared with control subjects without such a dietary intervention (+0.053 vs +0.036 g cm -2). The rate of increase, however, was significantly lower for girls than for boys (also by about 50%: +0.019 vs +0.038 g cm -2), possibly due to the more advanced bodily development of girls at this age. As the rate of increase of the bone mineral density is significantly decreasing for adolescents of this age group (20–35% in boys 16 yr of age when compared with 15 yr old ones, and 40–50% in girls), it can be predicted that such a dietary intervention starting at 15 yr of age will lead to an average level of the bone mineral values after 3–4 yr and even to an optimum level after 6–7 yr in boys with an originally subaverage level. However, such improvement is no longer feasible for girls at this age. The concentration of osteocalcin and parathyroid hormone as well as the activity of alkaline phosphatase in blood serum indicated that the higher than proportional increase of bone mineral density in the intervention group can be attributed to a decreased bone turnover which was caused by an increased intake of calcium through milk and dairy products.