Why is calcium important?
Calcium is essential for building and maintaining healthy bones throughout life. Calcium combines with other minerals to form hard crystals giving bones strength and structure. Almost 99% of the body’s calcium is found in the bones.
A small amount of calcium is absorbed into the blood and used for the healthy functioning of the heart, muscles, blood, and nerves. Bones act like a calcium bank. If you do not consume enough calcium rich foods in your diet, the body will take the calcium it needs from your bones for use in other parts of the body. Over time, this can reduce bone density (bone strength) and increase your risk of developing osteoporosis.
How much calcium is recommended?
Australian dietary calcium recommendations vary according to age.
| Lifestage | Age | Recommended Intake | Guidance |
| Children | 1-3 years | 500 mg per day | Growing bones require daily calcium intake. Daily dietary recommendations increase as children grow. |
| Children | 4-8 years | 700 mg per day | Growing bones require daily calcium intake. Daily dietary recommendations increase as children grow. |
| Girls & Boys | 9-11 years | 1,000 mg per day | Growing bones require daily calcium intake. Daily dietary recommendations increase as children grow. |
| Teenagers Girls & Boys | 12-18 years | 1,300 mg per day | Adequate calcium intake maintains bone strength. |
| Adults | 19 years + | 1,000 mg per day | Adequate calcium intake maintains bone strength. |
| Older Adults | Women 50 years + | 1,300 mg per day | The daily recommendation increases as calcium is less effectively absorbed from the intestine, and more can be lost through the kidneys.. |
| Older Adults | Men 70 years + | 1,300 mg per day | The daily recommendation increases as calcium is less effectively absorbed from the intestine, and more can be lost through the kidneys. |
Excessive calcium intake is not recommended. If calcium supplementation is used, it should only form part of daily requirements.
Calcium and food
Eating a calcium-rich diet is the best way to achieve recommended calcium intake. Calcium content in food varies, so it is important to consume ‘calcium-rich’ foods. Half of all Australian adults do not achieve their daily recommended calcium intake. Adding calcium to your diet is easy by focusing on food groups with higher calcium levels.
Calcium-rich foods examples
| Food type | Examples | Calcium range (mg per serve) |
| Dairy | Milk, cheese, yogurt | 150 – 305 mg per serve |
| Seafood | Trout, snapper, mussels, oysters, prawns, canned sardines or salmon | 35 – 300 mg per serve |
| Vegetables | Cucumber, kale, silverbeet, Chinese cabbage, broccoli rocket, watercress, bok choy, leeks | 59 – 250 mg per serve |
| Nuts & seed | Almonds, brazil nuts, hazelnuts, walnuts, sesame seeds, tahini paste | 28 – 75 mg per serve |
| Fruits | Orange, strawberries, figs, kiwi fruit, dates | 16 – 95 mg per serve |
| Other | Eggs, calcium-set tofu, canned chickpeas or soybean | 21 – 105 mg per serve |
| Meat | Pork chop, chicken | 21 – 105 mg per serve |
Discover calcium content in foods
Healthy Recipe Cookbook
Do we absorb all the calcium we eat?
Not all the calcium we consume is absorbed. A small amount of calcium will be lost and excreted from the normal body. This is factored into the recommended intake for your age.
Other factors can impact calcium absorption and should be discussed with your doctor, for example:
- Low vitamin D levels
- Excessive caffeine and alcohol intake
- Certain medical conditions (for example, coeliac disease, kidney disease)
Calcium supplements
It is best to obtain calcium from your diet. However, when adequate calcium intake is not possible, a supplement may be required as directed by your doctor or pharmacist. Healthy Bones Australia recommends 500-600 mg of supplement doses daily when required. This is considered safe and effective.
The most common calcium supplements are calcium carbonate, calcium citrate or hydroxyapatite. Supplements are available as oral tablets, effervescent tablets or soluble powder. Calcium supplements are usually well tolerated.
Calcium supplements are sometimes combined with vitamin D, as adequate vitamin D levels are important to assist the absorption of calcium in the body. Take supplements as directed, and talk to your doctor or pharmacist if you have any queries.
Diagnosed osteoporosis and calcium.
Calcium is essential for supporting your bone health. For people with diagnosed osteoporosis, calcium alone is not sufficient. Osteoporosis medication is generally required as directed by your doctor. It is common practice for doctors to prescribe calcium supplementation to accompany osteoporosis medication. Adequate calcium intake throughout adult life helps support bone health but may not prevent osteoporosis, as other factors can negatively impact bone health. See risk factors.
Questions and answers about calcium.
Why is calcium important for bones? How does it help my bones?
Calcium is stored in bones and helps give bone strength. Your body also needs calcium for other functions, so you will take calcium from the bones when your calcium intake is low. Adults unable to eat enough calcium may require a limited supplement to help top up calcium levels.
Why am I losing calcium? Can I rebuild bone strength?
You can lose calcium if you are not consuming enough daily calcium in your diet and your body takes what it needs from your bone storage. Also, when your vitamin D is low, you are not absorbing the calcium you eat.
You can rebuild bone strength by improving your diet, exercising and stopping negative factors.
What foods are high in calcium, and which are best for bones?
The foods high in calcium and best for bones include dairy (milk, cheese, yogurt), vegetables cucumber, kale, silverbeet, Chinese cabbage, broccoli, rocket, watercress, bok choy, leeks), seafood (trout, snapper, mussels, oysters, prawns, canned sardines or salmon) nuts & seeds (almonds, brazil nuts, hazelnuts, walnuts, sesame seeds, tahini paste) fruits (orange, strawberries, figs, kiwi fruit, dates) and other items such as eggs, calcium set tofu, canned chickpeas, soybeans. Even some meat (pork chop, chicken).
