Calcium has several important functions around the body, including helping build strong bones and teeth, regulating muscle contractions including the heartbeat, and ensuring that the blood clots normally.
It is thought that calcium may help lower high blood pressure and protect against colon and breast cancer, although more evidence is needed to confirm this.
A lack of calcium could lead to a condition called rickets, a condition that affects bone development, causing the bones to become soft and malformed, which can lead to bone deformities. Rickets in adults is known as osteomalacia, or soft bones.
Good sources of calcium include:
- milk, cheese and other dairy foods
- green leafy vegetables, such as broccoli, cabbage and okra, but not spinach
- soya beans
- soya drinks with added calcium
- bread and anything made with fortified flour
- fish where you eat the bones, such as sardines and pilchards
Adults need 700mg of calcium a day, and you should be able to get all the calcium you need from your daily diet. However, calcium supplements may be appropriate in some people, such as those at risk of osteoporosis.
Vitamin D is needed to aid absorption of calcium, so it is important to ensure that you get enough vitamin D, whether through exposure to sun, diet, or supplements.
Taking high doses of calcium could lead to stomach pain and diarrhoea, so if you take calcium supplements, do not take too much. The Department of Health advises that taking 1,500mg or less a day of calcium supplements is unlikely to cause any harm.