The researchers gathered information from 106 children, aged between three to five years at the beginning of the study, over a 12-year period. The families enrolled in the study were given food diaries to complete for the child and were asked to record everything the child ate and drank for several days each year.

The researchers used these diaries, along with information from the U.S. Department of Agriculture, to calculate the children's average daily intake of dairy and other foods.

At the end of the 12-year period, the authors assessed the bone health of the now adolescent study participants. Adolescents who had consumed two or more servings of dairy daily as children had higher levels of bone mineral content and bone density.

Even after adjusting for factors that affect normal bone development, including the child's growth, body size, and activity level, the authors found that these adolescents' average bone mineral content was 175g higher than the adolescents who had consumed less than two servings of dairy products daily.

Researchers also evaluated the combined effects of dairy products and other foods consumed by the participants. Moore said "children who consumed two or more servings of dairy and four ounces of meat or other non-dairy protein had bone mineral contents over 300g higher than those children with lower intakes of both dairy and other proteins."

Moore pointed out that "dairy is a key source of proteins, calcium, and other micronutrients including phosphorus and vitamin D".

The study is scheduled for publication in The Journal of Pediatrics.

From the August 30, 2010, Prepared Foods E-dition