Calcium, the most abundant mineral in the body, is found in some foods, added to others, available as a dietary supplement, and present in some medicines (such as antacids).

There is more calcium in the body than any other mineral and it has several important functions.

These include:

  • helping build strong bones and teeth
  • regulating muscle contractions, including heartbeat
  • ensuring 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 in children or osteoporosis in later life.
Good sources of calcium

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
  • tofu
  • soya drinks with added calcium
  • nuts
  • bread and anything made with fortified flour
  • fish where you eat the bones, such as sardines and pilchards

How much calcium do I need?

  • Adults need 700mg of calcium a day.
  • You should be able to get all the calcium you need from your daily diet.

What happens if I take too much calcium?

  • Taking high doses of calcium (over 1500mg a day) could lead to stomach pain and diarrhoea.

  What does the Department of Health advise?

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

References:

http://www.nhs.uk/Conditions/vitamins-minerals/Pages/Calcium.aspx

http://www.webmd.com/vitamins-supplements/ingredientmono-781-CALCIUM.aspx?activeIngredientId=781&activeIngredientName=CALCIUM

http://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/

http://en.wikipedia.org/wiki/Calcium