Calcium & magnesium are the major components of bone matter & are essential minerals to maintain healthy & strong bone structure. Magnesium also plays a vital role in the proper absorption & distribution of calcium. Zinc is necessary for the healthy growth of bone tissue & the immune system. Calcium, magnesium & zinc also play an important role in maintaining a healthy nervous & muscular function. Elderly people, post-menopausal women, growing children, vegetarians & vegans may have an increased dietary requirement for bone building minerals.