Calcium is important for healthy tissue, where it is used for proper nerve and muscle function, cell signaling and blood clotting. The main mineral found in bones is calcium phosphate, and it is important for bone strength. The best sources of calcium phosphate in the diet are enriched cow milk and dairy products made from enriched milk. Calcium is so important to health that many foods have been enriched with calcium, including cereal and juices, especially orange juice. Soy products, such as soy milk, soy beans and tofu, also have high levels of calcium.
The main minerals of bone tissue are calcium and phosphorus. This is why calcium phosphate is important to the diet of children and adolescents — it allows the bones to grow and strengthen. Much of the calcium in the bones is stored before early adulthood.
When the body runs low in calcium, it is taken from the bones. Over time, this will weaken the bones and make them more brittle and breakable. Low calcium in the body can also cause muscle pain and spasms as well as numbness. Calcium has been proven to help heart health, prevent colon and rectal cancer and possibly lower cholesterol levels.
Calcium is readily found in milk and dairy products made from milk, which is one reason why dairy is an important staple in nutrition for children, whose bones are still growing. Yogurt actually has a slightly higher calcium level than milk itself. Cheeses produced with more milk, especially Swiss cheese and ricotta cheese, are higher in calcium. Varieties of cheese made from goat and sheep milk are another source of calcium. Milk sugar, which is called lactose and is found in these dairy products, is not tolerated by all adults, so other calcium sources might be needed in the diet.
Soy products, which do not contain lactose, are another good course of calcium phosphate. This would include soy milk, edamame and tofu. There are other calcium phosphate sources that might be surprising. Some types of seafood, such as salmon, sardines, anchovies, clams and oysters, are good sources of calcium. Artichokes, leafy green vegetables, molasses and broccoli are also good sources of calcium.
Calcium-enriched foods, mostly notably enriched juices such as orange juice, have become common. The calcium phosphate in them is similar to that in calcium pills. These products provide alternative sources of calcium in the diet.