Calcium

Calcium is a mineral. It's vital for developing and maintaining healthy bones and teeth throughout your life.

A small amount of calcium is absorbed into your blood and is important for muscle and nerve activity in your body, including for your heartbeat.

Eating a diet rich in foods containing calcium is the best way to get enough.

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Calcium is stored in your bones

Your skeleton contains 99% of your body’s calcium. Calcium is deposited in your bones until your mid-20s. 

• Your bone mass increases about 7-fold from birth to puberty and a further 3-fold during adolescence.
• It then remains stable until about 50 of age in men or until women reach menopause. 
• Bones act as a calcium bank. If there's not enough calcium in your diet, your body will take what's needed from your bones for use in other parts of your body. 

Calcium deficiency

Calcium deficiency in children will stunt their growth and result in poor quality teeth and bones and an increased risk of fractures. Adults will experience aches and pains, lose height and develop brittle bones (osteoporosis).(external link)

Dairy foods

• Dairy products such as cow’s milk, yoghurt and cheese are the richest source of calcium.
• A glass of milk (250 mL) contains about 300 mg calcium.
• Low and reduced-fat milk and yoghurt are best to help reduce your intake of saturated fat and total energy.
• Goat's and sheep milk have similar nutrition to cow’s milk and are also a good source of calcium.
• Butter, cream, cream cheese and sour cream are made from milk fat so have high levels of saturated fat and are low in protein and calcium. 

Other food sources of calcium

• Plant-based milks made from soy, rice, oats or nuts (eg, almonds, cashews) are an alternative to cow’s milk. These milks are not naturally high in calcium. Always look for a product that's had calcium added (at least 120 mg calcium per 100 mL).
• Canned salmon and sardines due to their soft, edible bones.
• Tofu and tempeh (fermented soybean) made from soybeans.
• Dark, leafy, green vegetables such as kale, spinach, cabbage, broccoli and bok choy.
• Nuts and seeds such as Brazil nuts, almonds, hazelnuts, chia seeds, flaxseed, sesame seeds.

• Fortified foods such as some cereals, oats, breads and other foods which may have calcium added. Check the label to see if they do, as this can help boost your calcium levels.

Note: Foods sources such as spinach, rhubarb, beans, seeds, nuts and whole grains also contain oxalic or phytic acid which reduces the amount of calcium that can be used by the body.

Calcium content of different foods

Here are the recommended dietary intakes (RDIs) of calcium for people of different age groups:

• Babies (0–6 months): 210 mg
• Babies (7–12 months):  270 mg
• Children (1–3 years): 500 mg
• Children (4–8 years): 700 mg
• Children (9–11 years): 1,000 mg
• Children (12–18 years): 1,300 mg
• Adult men (19–70 years): 1,000 mg
• Older adult men (over 70 years): 1,300 mg
• Adult women (19–50 years): 1,000 mg 
• Adult women (over 50 years): 1,300 mg
• Pregnant and breastfeeding people (14–18 years): 1,300 mg
• Pregnant and breastfeeding people (19+ years): 1,000 mg

• Children and young people: Calcium is particularly important for children and young people because their bones are growing rapidly.
• Older men and women: Bone loss speeds up with the hormonal changes following menopause and with age. This means women after menopause and men over 70 years of age have higher calcium needs. Weight-bearing exercise and vitamin D (which helps your body to absorb calcium from your diet) also help to maintain bone strength.
• People who exclude dairy: People following a vegan diet or excluding dairy foods due to a milk allergy or lactose intolerance need to carefully include plenty of non-dairy sources of calcium.
• People who smoke, drink excessive amounts of caffeine or have high salt or protein intakes: These can cause calcium loss from your body.

It's best to get calcium from foods because of the other nutrients obtained. However, sometimes when there's not enough calcium in your diet for your body's needs then taking a calcium supplement may be necessary – especially if you're at risk of developing osteoporosis.

If you’re thinking about taking a calcium supplement, talk to your healthcare provider or pharmacist first as it may interact with other medicines you’re taking.

Menopause and calcium supplements

During menopause you have an increased risk of osteoporosis and bone fracture. Read more about osteoporosis.

If you are postmenopausal, a high calcium intake (more than 1,300 mg per day) will slow the rate of bone loss and may reduce the risk of fracture. However, it is not proven that getting your calcium from supplements will have this effect.

There is some evidence suggesting that there may be an increased risk of heart attacks and other cardiovascular problems for postmenopausal women taking calcium supplements. However, the research in this area is inconsistent. It's best to look at food as the first option for increasing your calcium intake and discuss the benefits and risks of calcium supplements with your healthcare provider.

Read more about calcium supplements.

• Include milk, yoghurt and cheese in meals and snacks and aim for 2 to 3 serves per day.
• Choose low and reduced-fat versions to reduce your intake of saturated fat and energy.
• Choose plain yoghurt instead of flavoured or sweetened versions. Have it on top of breakfast, as a snack or dessert.
• Choose non-dairy yoghurt, cheeses and milks, or other food products with added calcium (calcium-fortified). You'll see calcium in the ingredients list and on the nutrition label. 
• Have small amounts of raw, unsalted almonds as a healthy snack.
• Make meals with foods containing calcium, such as a green leafy salad with 45 g tinned salmon as a quick lunch.
• Eat a varied diet with food from the 4 food groups which will mean that you are naturally including a wide range of foods containing calcium including dairy foods, vegetables, fruit, nuts, seeds, legumes etc.

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