Calcium
Calcium is essential for strong bones and teeth. It also plays an important role in muscle contractions, blood clotting, and sending and receiving nerve signals.
Sources
The best sources of calcium are milk, milk products and calcium-fortified soy and other milk substitutes. Other good food sources of calcium include:
- leafy green vegetables such as broccoli, cabbage, kale and bok choy,
- tofu (depending on the type) and tempeh,
- tinned fish (with edible bones such as sardines),
- nuts and seeds such as brazil nuts, almonds and sesame seed paste (tahini), and
- calcium-fortified foods such as breakfast cereals, juices and bread.
Calcium from some of these foods may not be as well absorbed in the body, due to certain substances in the food such as oxalates in spinach, and phytates in nuts, seeds and grains, which bind the calcium.
Requirements
The recommended amounts of calcium below reflect how much most people need. Requirements vary at different life stages because:
- babies fed on formula need more calcium than breastfed babies as calcium from formula is not as well absorbed as in breast milk,
- children and teenagers need more calcium to support growth and build peak bone mass,
- older people, particularly women after menopause, need more calcium to help slow down the natural loss of bone that happens with aging.
| Recommended amounts (mg/day) | |
| Infants | |
| Breast-fed | 210 |
| Formula-fed | 350 |
| Children | |
| 7-12 months | 270 |
| 1-3 years | 500 |
| 4-8 years | 100 |
| 9-13 years | 1,000-1,300 |
| Adolescents (14-18 years) | 1,300 |
| Adult men | |
| Up to 70 years | 1,000 |
| > 70 years | 1,300 |
| Adult women | |
| Up to 50 years | 1,000 |
| Pregnancy | 1,000 |
| Lactating | 1,000 |
| > 50 years | 1,300 |
Deficiency
If you do not get enough calcium in your diet, your body will take calcium from your bones. If this happens over a long period of time, you may develop a condition called osteoporosis. People who have osteoporosis usually do not realise they have developed this condition until their bones become so weak that they easily break.
You can help keep your bones stay strong and healthy by making sure you are getting enough calcium in your diet, enough vitamin D from the sun, and exercising regularly.
Safety
If you are getting more calcium than you need over a long period of time, you may develop kidney stones or stiff muscles.
Disclaimer
The content displayed on this webpage is intended for informational purposes and is a guide only. It does not replace or substitute for professional medical advice, diagnosis or treatment.
Information contained on this webpage must be discussed with an appropriate healthcare professional before making any decisions or taking any action based on the content of this webpage.
Sources
National Health and Medical Research Council
http://www.nrv.gov.au/nutrients/calcium
Better Health Channel
http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Calcium
Medline Plus Medical Encyclopaedia
http://www.nlm.nih.gov/medlineplus/ency/article/002412.htm
Dietitians Association of Australia
http://daa.asn.au/?page_id=772
NIH Osteoporosis and Related Bone Diseases National Resource Centre
http://www.niams.nih.gov/Health_Info/Bone/Osteoporosis/overview.asp
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