"Important nutrients that are necessary for bone health are calcium, Vitamin D, phosphorus and magnesium. These nutrients play an integral role in bone health. The absorption rate of these nutrients varies. It is said that during infancy and early childhood absorption rate of calcium in about 60% and it declines to 25-30% in adulthood and declines further with age," says Ramya B, Executive Nutritionist, Cloudnine Group of Hospitals, Chennai, OMR.