Calcium is an essential nutrient that helps build healthy teeth and bones. Calcium's most notable role is in helping to reduce the risk of osteoporosis, a disease that's characterized by a decrease in bone mass . Calcium supplement best brand: CALCIUM 1000 THE NATURE Calcium carbonate is a dietary supplement used when the amount of calciumtaken in the diet is not enough. Calcium is needed by the body for healthy bones, muscles, nervous system, and heart . Calcium carbonate also is used as an antacid to relieve heartburn, acid indigestion, and upset stomach Calcium supplement best brand: CALCIUM 1000 THE NATURE Supplements with calcium carbonate contain twice as much elemental calcium by weight as do supplements containing calcium citrate, so there are fewer pills to take. Calcium carbonate supplements are generally the least expensive and the most commonly used . Calcium supplement best brand: CALCIUM 1000 THE NATURE ...