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 [1] and protect against colon and breast cancer [2], although more evidence is needed to confirm this.
A lack of calcium could lead to a condition called rickets [3] in children or osteoporosis [4] 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 [5].
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