Calcium can bind to a wide range of proteins altering their biological activity. This is important in nerve impulse transmission and muscle contraction. Calcium is also needed for blood clotting, activating clotting factors. Vitamin D is needed for absorption of dietary calcium and so calcium deficiency may be linked with rickets in children . This may be related to repeated pregnancy with lengthy breast feeding.
Osteoporosis can be due to calcium deficiency.
This involves loss of calcium from the bones and reduced bone density. This causes bones to be brittle and liable to fracture. Bone loss occurs with age in all individuals. This usually occurs after 35-40 years and involves the shrinking of the skeleton. Bone loss is greatest in women following the menopause.