Abstract
During the last decade the focus of osteoporosis prevention moved toward understanding the importance of maximizing peak bone mass early in life. The role of nutrition, physical activity, and genetics in the attainment of peak bone mass is currently a major focus of osteoporosis research. Calcium intake and physical activity play important roles in the development of peak bone mass. Genetics also plays an important role and may interact with diet and activity in its effect on bone. Future studies on how diet, activity, and genetics interact with each other will provide important insights into the development of peak bone mass.