Calcium protects the bones and teeth from lead by inhibiting absorption of this toxic metal. If there is a calcium deficiency, lead can be absorbed by the body and deposited in the teeth and bones. Deficiencies of calcium are also associated with cognitive impairment, convulsions, depression, delusions, and hyperactivity. The amino acid lysine is needed for calcium absorption. Food sources of lysine include cheese, eggs, fish, lima beans, milk, potatoes, red meat, soy products, and yeast.
Lysine is also available in supplement form.
Female athletes and menopausal women need greater amounts of calcium than other women because their estrogen levels are lower. Estrogen protects the skeletal system by promoting the deposition of calcium in bone. Heavy exercising hinders calcium uptake, but moderate exercise promotes it. Insufficient vitamin D intake, or the ingestion of excessive amounts of phosphorus and magnesium, also hinders the uptake of calcium. Taking calcium with iron reduces the effect of both minerals.