Consistency Critical in Calcium Benefits

SHEFFIELD, EnglandCalcium supplementation can enhance bone mineral accrual in young girls; however, consistency appears to be the key, according to researchers from the University of Sheffield (Am J Clin Nutr. 2008;87(2):455-62). Their 18-month randomized trial of calcium supplementation (762 mg/d), with follow-up two years after supplement withdrawal, involved 96 girls (mean age 12 years) with low calcium intakes at baseline. The mean additional calcium intake in the supplemented group was 555 mg/d. Compared with the control group at the end of intervention, girls taking calcium had significantly greater increases in bone mineral density (BMD) and bone mineral content (BMC) at all skeletal sites; concentrations of bone resorption markers were also significantly lower. However, two years later, the gains in BMC and BMD were no longer evident, which the researchers suggested means calcium supplementation supports bone health by suppressing bone turnover, an effect that is reversed upon ending supplementation.