Calcium has several important functions.

These include:

• helping build bones and keep teeth healthy
• regulating muscle contractions, including your heartbeat
• making sure blood clots normally

A lack of calcium could lead to a condition called rickets in children, and osteomalacia or osteoporosis in later life.

Sources of calcium include:

• milk, cheese and other dairy foods
• green leafy vegetables – such as curly kale, okra but not spinach (spinach does contain high levels of calcium but the body cannot digest it all)
• soya drinks with added calcium
• bread and anything made with fortified flour
• fish where you eat the bones – such as sardines and pilchards

Adults aged 19 to 64 and over need 700mg of calcium a day.

You should be able to get all the calcium you need from your daily diet.

Taking high doses of calcium (more than 1,500mg a day) could lead to stomach pain and diarrhoea.

You should be able to get all the calcium you need by eating a varied and balanced diet.

If you take calcium supplements, do not take too much as this could be harmful.

Taking 1,500mg or less a day is unlikely to cause any harm.