Calcium (Ca) is a grey silvery metal that is rather hard. It is the fifth most abundant element in the earth’s crust and makes up more than 3% of the crust. Calcium is obtained from chalk, limestone, and marble and is only found in living organisms.

Sir Humphrey Davy discovered calcium in 1808. Calcium is used for maintaining healthy bones and teeth. It is also sometimes claimed to be useful for treating heartburn and indigestion.
Dairy products are an excellent source of calcium. Vitamin D is needed to absorb calcium. 99% of the body’s calcium is stored in your bones and teeth. Research has shown that increasing calcium in your diet can help lower your blood pressure. For most people, three servings of milk or milk products daily are recommended. One serving provides approximately 300 mg of calcium.