Building Strong Bones: How Does Calcium Reduce Osteoporosis Risk?
Calcium helps build and maintain strong bones, but its role goes well beyond your skeleton. Your muscles, nerves and heart also rely on it to function properly.
So, how much calcium do you need, which foods are good sources, and can you get enough without dairy? Here’s what to know about supporting your bone health at every age.
Why is calcium important?
Calcium is the most abundant mineral in the body. Most is stored in your bones and teeth, where it provides strength and structure. It also supports muscle contraction, nerve signalling and blood clotting.
When you regularly miss out on enough calcium, your body can draw on the calcium stored in your bones. Over time, this can contribute to bone loss and increase your risk of osteoporosis. However, calcium intake is only one of several factors that affect bone health.
What is osteoporosis?
Osteoporosis is a condition in which bones become less dense and more fragile, making them more likely to break. It is often called a “silent disease” because there may be no obvious symptoms until a fracture occurs.
Osteopenia means bone density is lower than normal but has not reached the osteoporosis range. It does not inevitably progress to osteoporosis; your individual risk factors help determine the monitoring and treatment you need.
Osteoporosis can be treated. Appropriate medical treatment can improve bone density and reduce fracture risk, alongside adequate calcium, vitamin D and suitable exercise. Calcium alone is not a treatment for osteoporosis.
Can a blood test tell me if my bones are healthy?
A normal blood calcium result does not rule out osteoporosis. Your body tightly controls blood calcium levels, so they do not reliably reflect how much calcium is stored in your bones.
If you have risk factors for osteoporosis, your GP may recommend a bone density scan, also called a DXA or DEXA scan, as part of your assessment.
How much calcium do you need each day?
Your calcium requirements depend on your age and stage of life. The Australian recommended dietary intakes (RDIs) are:
Age or life stageCalcium per dayChildren 1–3 years500 mgChildren 4–8 years700 mgChildren 9–11 years1,000 mgTeenagers 12–18 years1,300 mgAdults 19–50 years1,000 mgWomen 51–70 years1,300 mgMen 51–70 years1,000 mgAdults 71 years and older1,300 mg
Calcium is especially important during childhood and adolescence, when bones are growing. Requirements also increase for women from age 51 and all adults from age 71.
Do you need more calcium during pregnancy or breastfeeding?
Australian calcium recommendations do not increase during pregnancy or breastfeeding: they remain 1,000 mg daily for adults and 1,300 mg for teenagers aged 14–18.
During pregnancy, the body becomes more efficient at absorbing calcium. Breastfeeding can temporarily reduce bone mineral density, but this generally recovers after weaning. Meeting your usual calcium requirements remains important.
What foods are good sources of calcium?
Milk, yoghurt and cheese are useful calcium sources. Dairy-free options include calcium-fortified plant milks, calcium-set tofu and canned fish with edible bones.
Other foods, including kale, broccoli, almonds and chickpeas, can contribute, but their calcium content and absorption vary.
Food or drinkPractical way to include itMilkAdd to porridge, cereal or a smoothieYoghurtEnjoy with fruit or as a snackCheeseAdd to sandwiches, toast or saladsCalcium-fortified plant milkUse in breakfast cereal, smoothies or cooking; check the calcium content on the labelCalcium-set tofuAdd to stir-fries, curries or scrambled tofuCanned sardines or salmon with edible bonesMash into sandwich fillings or add to saladsKale, broccoli and bok choyInclude in stir-fries, soups and side dishesAlmonds and chickpeasAdd to snacks, salads or meals for an extra contribution
Can you get enough calcium without dairy?
Yes, but it helps to plan your choices. Look for plant milks with added calcium and check labels, as products vary considerably. The same applies to plant-based yoghurts and cheeses.
Build meals around reliable sources, such as fortified drinks and calcium-set tofu, with vegetables, legumes and nuts contributing across the day. Calcium absorption also varies between foods, so variety matters.
Simple ways to add calcium to your day
Small changes can make calcium-rich foods easier to include:
At breakfast: make porridge with milk or calcium-fortified plant milk.
At lunch: add cheese to a sandwich or try canned salmon with its softened edible bones.
For a snack: enjoy yoghurt with fruit.
At dinner: include calcium-set tofu in a stir-fry with broccoli or bok choy.
These ideas are starting points. The portions and combinations you need will depend on your daily calcium target and the products you choose.
Do you need a calcium supplement?
Not everyone needs a supplement. Food is usually the first option, but supplementation may help if you cannot meet your requirements through your diet.
A dietitian can assess your intake and identify any shortfall. Your GP or pharmacist can help determine whether a supplement is appropriate and how it fits with your medical care.
What else helps keep bones strong?
Adequate Vitamin D helps your body absorb calcium. If you are at risk of deficiency, speak with your GP about assessment and whether supplementation is needed.
Bones respond to the demands placed on them. Weight-bearing activities and progressive resistance training help support bone strength, while balance exercises can help reduce falls.
The right exercise depends on your fitness, health and fracture risk. If you have osteoporosis or a previous fracture, a physiotherapist or exercise physiologist can help you choose suitable activities and progress safely.
Bone health is influenced by more than food and exercise. Family history, menopause, certain medical conditions and some medications can also affect your risk. Discuss concerns with your GP, particularly if you have broken a bone after a minor fall or injury.
Need help meeting your calcium needs?
Whether you avoid dairy, follow a plant-based diet or want support after an osteopenia or osteoporosis diagnosis, practical food changes can help you meet your nutritional needs.
At Health Management Dietitians, our Accredited Practising Dietitians in Cairns, Atherton and Mareeba provide personalised advice that fits your preferences, health needs and everyday routine. Online consultations are also available.
At Health Management Dietitians, we can help tailor your nutrition to your preferences and nutritional needs — helping you eat as comfortably and confidently as possible while reducing the risk of nutritional deficiencies.
We understand that nutrition isn’t one-size-fits-all. Our Cairns, Atherton and Mareeba dietitians provide personalised, practical nutrition advice to help you reach your goals while still enjoying food.