Calcium is a natural chemical element that is essential for all living organisms. Although calcium has been known for thousands of years it wasn’t isolated until 1808 by Cornish chemist and inventor, Sir Humphry Davy.
In its pure elemental state calcium is a soft, silvery-white alkaline earth metal. Calcium is never found in this isolated state in nature but exists instead in compounds.
Calcium is the fifth most abundant element in the human body (after oxygen, carbon, hydrogen and nitrogen) and it is known to support healthy teeth, bones and other skeletal tissue. Humans require a certain level of calcium to maintain healthy communication between the brain and other parts of the body.
Calcium in your diet
Because your body doesn’t produce calcium, you must get it through other sources such as food or supplements.
Calcium can be found in a range of foods, including:
- Dairy products
- Fish with edible soft bones (such as sardines)
- Dark green leafy vegetables (such as kale and broccoli)
- Calcium fortified foods and drinks such as cereal and fruit juices, soy products, and milk substitutes.
Calcium in Supplements
Even if you eat a balanced, healthy diet you may find it difficult to get enough calcium. Certain situations could call for a calcium supplement such as:
- Having osteoporosis
- Following a vegan diet
- Consuming large amounts of protein or sodium
- Having certain bowel or digestive diseases
- Being lactose intolerant
- Receiving long-term treatment with corticosteroids
The two main forms of calcium supplements are citrate and carbonate. Calcium carbonate is used to prevent and treat osteoporosis and relieve the symptoms associated with indigestion. Calcium citrate can be used to treat osteomalacia/rickets (weak bones), hypoparathyroidism and a muscle disease known as latent tetany.
Your body needs vitamin D in order to absorb calcium. You can get vitamin D from fortified foods, sun exposure and other foods that contain small amounts of vitamin D such as egg yolks and fatty fish (like salmon, tuna and mackerel.)
The recommended daily allowance for vitamin D is 15 micrograms for most adults.