Girls' calcium intake is associated with bone mineral content during middle childhood.

We examined longitudinally the association between calcium intake and total body bone mineral content (TBBMC) in 151 non-Hispanic white girls. Intakes of dairy, energy, and calcium were assessed using three 24-h dietary recalls in girls at ages 5, 7, 9, and 11 y. We assessed their total-body bone mineral content with dual-energy X-ray absorptiometry at ages 9 and 11 y. Dairy foods comprised the major contributor (70%) to calcium intake over the 6-y period; 28% of calcium came from other foods, and 2% from supplements. By age 9 and 11 y, the majority of girls did not meet calcium recommendations. Higher calcium intake at ages 7 and 9 y was associated with higher TBBMC at age 11 y. Calcium intake at age 9 y was also positively associated with TBBMC gained from age 9 to 11 y. Calcium intake at age 11 y was not correlated with TBBMC at the same age. Relations between calcium intake and TBBMC did not differ for total calcium and for calcium from dairy sources, likely reflecting the fact that dairy products were the major source of calcium in this sample. Results from the present study provide new longitudinal evidence that calcium intake, especially calcium from dairy foods, can have a favorable effect on girls' TBBMC during middle childhood.