Maintains normal heartbeat, nerve and muscle function and blood clotting. Milk products, green leafy vegetables canned salmon with bones and sardines with bones, calcium-fortified orange juice, corn tortillas processed with lime.
Calcium decreases the absorption of iron supplements unless vitamin C is taken at same time.
Increases blood level of both calcium and magnesium-containing medications or supplements. Oral contraceptives and estrogens may increase calcium absorption. Potassium supplements increases chance of heartbeat irregularities. Decreases absorption of tetracycline. Mega-doses of vitamin A stimulates bone loss.