Calcium helps regulate nerve and muscle function and is the major mineral component of bones. It is necessary to build strong bones and is important for building a strong skeleton, maintaining normal blood pressure and preventing cancers of the digestive tract. The main sources of calcium in the American diet are dairy products, but there are other foods rich in calcium - greens like collards, mustard, kale, and bok choy, canned salmon and sardines, tofu that has been coagulated with a calcium compound, calcium fortified soy milk and fruit juice, blackstrap molasses, and broccoli. Calcium supplements may also be used to get the 1,000 to 1,200 mg a day (from all sources) that is recommended for women. I don't recommend calcium supplements for men. Calcium citrate is the best form of this mineral because it more easily absorbed than other forms. Do not use bone meal or dolomite as calcium sources because they may be contaminated with lead and other toxic heavy metals.