Researchers at the University of Tennessee report that adequate calcium intake, lean body mass and physical activity are the three most important factors in maintaining healthy bone mineral density (BMD) and bone mineral content (BMC)—both factors in determining osteoporosis risk.

In a study of 42 women around the age of 21 and of various weights, the researchers evaluated BMD at several sites throughout the body and obtained a history of the participants’ physical exercise and calcium intake. In this study, lean body mass was found to be the most important factor for predicting total body bone mineral density. However, BMD in the spine was most influenced by exercise and calcium intake.

Another study indicates that even for older women, maintaining a healthy body weight, physical activity and adequate calcium helps preserve bone mass. Finnish researchers focused on how lifestyle factors and weight changes might influence the rate of bone loss in the neck. Altogether 128 women from 60 to 65 years of age were evaluated over a five-year period. The women were divided into four groups: high and low physical exercise, and high and low calcium intake. They were asked to perform strength tests and underwent bone density testing. The researchers found that higher calcium intake and regular physical fitness was associated with a smaller decrease in bone mineral content in the neck.

Sources: J Women’s Health Gend Based Med 2002 May;11(4):389-98; Osteoporosis Int 2001;12(5):373-9