Calcium

What is calcium?
Calcium is one of the most important elements that your body needs in order to live. Calcium makes up most of your bones, and without enough calcium, it is easy to break your bones. Calcium is also the 5th most abundant element in the Earth's crust, making up 3% in the oceans and soils.

Vitamin D is the essential vitamin for calcium absorption by the human body. Vitamin D is transferred to a hormone which causes intestinal proteins, the ones responsible for calcium absorption, to be produced.

While calcium and its compounds are not considered to be toxic, ingesting too much calcium carbonate or antacids can cause milk-alkali syndrome, which is associated with hypercalcemia sometimes leading to fatal renal failure. Excessive consumption would be on the order of 10 g calcium carbonate/day, though symptoms have been reported upon ingesting as little as 2.5 g calcium carbonate daily.

The element is also essential for animal and plant nutrition. Calcium participates in many biochemical reactions, including building skeletal systems and moderating muscle action for animals. Also, animals need a good amount of calcium to survive. Weak bones can snap very easily, and to have strong bones you need to have a lot of calcium. Too much calcium can also be fatal to animals.

Where is calcium found?
Calcium isn't found free in nature, but it can be purified into a soft silvery-white alkaline earth metal from its natural form, which it the silver/grey metal seen above. Calcium is also found in the oceans and soils of the world, as mentioned above. As for its uses, calcium is used in many important everyday objects and foods, including:

• Many dairy products, such as cheeses, yogurts, and milk
• Cement
• Removing nonmetallic impurities from alloys
• A reduction agent in the preparation of other metals

A few little known facts about calcium:

1. Pure Calcium Metal reacts vigorously and sometimes violently when mixed with water and acids.
2. The element name "calcium" comes from the Latin word "calcis" meaning "lime".
3. Calcium has been known since the 1st century, when the ancient Romans were known to make lime from calcium oxide.
4. Though calcium has been known for thousands of years, it was not purified as an element until 1808 by Sir Humphrey Davy