Several clinical trials reveal the positive effects of combined supplemental calcium and vitamin D for bone health. Vitamin D is important for its ability to promote intestinal calcium and phosphorous absorption, reduce urinary calcium loss and enhance healthy bone composition. In a large trial published in the New England Journal of Medicine involving over 3,000 women, supplementation with calcium and vitamin D daily for one and a half years supported bone composition of the femur. In another study, calcium and vitamin D supplementation promoted calcium utilization and maintained healthy bones in postmenopausal women. Calcium citrate malate combined with vitamin D moderated the rate of bone loss for a separate group of postmenopausal women, maintaining support for the spine. Calcium and vitamin D also play roles in cardiovascular and colon health.