Calcium requirements of physically active people

Dietary calcium and physical activity have been independently, but inconsis tently, associated with the development of increased peak bone mass and red uced bone loss later in life. An examination of the literature points to im portant effects of dietary calcium on bone health. During the development o f peak bone mass, calcium intakes of <1 g/d are associated with lower bone mineral density. At intakes approaching calcium requirements, physical acti vity is a mon important predictor of bone mineral density than is calcium i ntake. In studies of postmenopausal women, calcium intakes of 1 g (25 mmol/ dj appear to be necessary to effect a positive impact of exercise on bone m ineral density in the spine. Calcium intakes recommended for protecting bon e health appear to be adequate to protect against other disorders with an e tioIogy that includes inadequate dietary calcium. Calcium requirements as m odified by physical activity need to be determined for each population subg roup according to sex, age, race, and cultural environment.