Calcium is the most abundant mineral in the human body, comprising over 1.5% of the total body weight. About 99% of the body's calcium is found in the bones, with 1% occurring in the soft tissues. Calcium absorption is vitally dependent upon vitamin D. Calcium is involved in the structural formation of bones and teeth. It is also needed for 'normal' communication amongst nerve cells, for blood clotting, wound healing and for muscle contraction. Calcium has also been shown to be beneficial in protection from osteoporosis which is usually related to post-menopausal women.