Calcium is often helpful for menstrual problems, particularly menstrual cramps, irritability or apprehension, and muscle cramps that occur around menstruation. The recently recognized premenstrual syndrome is often helped in part with additional calcium, though magnesium supplementation may be even more important. In some cases, however, reducing calcium intake can be helpful. Generally, muscle cramps or leg and foot cramps can be helped by calcium and vitamin D. Also, some cases of hyperkinesis in children, when associated with calcium deficiency, may be helped by supplementation.

Other problems related to bone health affect the mouth, jawbone, and teeth. In some cases, calcium may be helpful for problems of loose teeth, gingivitis (gum inflammation), and periodontal disease. Usually 1,000 mg. of calcium supplemented in the diet along with a dietary intake of phosphorus ranging from 1,000-2,000 mg. is suggested.

Calcium is often used to reduce heart irregularity; along with magnesium, it helps regulate heart contraction and relaxation. Through increasing contractility, calcium can help in congestive heart failure. Additional calcium may protect us from the toxicity of cadmium, rubidium, or mercury exposure by competing for absorption. Proper calcium intake may reduce the incidence of colon and rectal cancers through forming insoluble soaps with some mild carcinogens produced in the body, including bile acids and free, ionized fatty acids. A good calcium-phosphorus ratio in the diet also reduces the risk of cancer in the large intestine.

Deficiency and toxicity: In general, a high calcium intake for brief periods does not cause any problems, as excesses are usually eliminated in the urine and intestines. With magnesium deficiency, though, high amounts of calcium or vitamin D can lead to calcification of the soft tissues or to kidney stone formation. It is possible that prolonged high amounts of calcium (higher than a 2:1 calcium-phosphorus ratio) and supplemental vitamin D can lead to abnormal calcification of long bones in children or to hypercalcemia (high blood calcium levels) and soft tissue calcification in adults, as well as a decrease in bone strength. Also, if the parathyroid glands are not functioning well, calcium can accumulate and cause problems.

Calcium itself is thought to be one of the concerns in atherosclerosis, forming part of the plaque laid down in the arteries. Guy Abraham, M.D., who is known for his work in premenstrual syndrome, expressed a real concern over routine calcium supplementation in our society as he feels it exacerbates the degenerative process in the blood vessels, kidneys, and other organs and tissues. It is possible that these problems of calcium excess are not specifically related to dietary calcium but rather to calcium's metabolism in relationship to the endocrine system. More research is clearly needed in this area. This potential toxicity concern makes me realize that it is important to be very aware of calcium metabolism and individual needs and to not just blindly supplement it as is so common recently.

Still, though, calcium deficiency is a more common concern in our culture than is excess calcium. This is especially true for the elderly, for alcoholics, for pregnant women, and for people with gastrointestinal disease. The "standard" American diet does not meet the normal calcium requirements; part of this problem is due to high phosphorus levels in the diet. Phosphorus is found in most foods, but soda pops, diet pops, meats, eggs, and processed foods such as lunch meats and cheese spreads contain especially high amounts. The ideal dietary phosphorus-calcium ratio is about 1:1. The ratio in the average American diet is often greater than 2:1 and sometimes even 4:1 or 5:1. At those levels, excess calcium is removed from bone and eliminated, blood levels are reduced, and there is bone demineralization. A diet high in phosphorus and low in calcium has been shown to cause bone loss and increase tissue calcification.