August 21/Law & Health Weekly -- Dairy is recognized as a key component of a healthy, balanced diet. However, until recently it was unclear how long-term dairy intake contributes to the many aspects of bone health in children, including bone density, bone mineral content, and bone area. A new study soon to be published in The Journal of Pediatrics investigates the effect of childhood dairy intake on adolescent bone health.

Dr. Lynn Moore and colleagues from Boston University School of Medicine analyzed data from the Framingham Children's Study in an effort to understand the relationship between childhood dairy intake and adolescent bone health. The researchers gathered information from 106 children, 3-5 years of age 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 United States 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. They found that the adolescents who had consumed two or more servings of dairy per day 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 per day.

The researchers also evaluated the combined effects of dairy and other foods consumed by the study participants. According to Moore, "Children who consumed two or more servings of dairy and 4oz of meat or other nondairy protein had bone mineral contents over 300g higher than those children with lower intakes of both dairy and other proteins."

The study highlights the importance of dairy intake throughout childhood, and  Moore points out that "dairy is a key source of proteins, calcium and other micronutrients including phosphorus and vitamin D."

From the September 2, 2008, Prepared Foods e-Flash