A glass of milk, tub of yoghurt, slice of cheese or a scoop of ice-cream, these are all sources of dairy and they contains high levels of calcium. These dairy foods are often the ‘go-to’ to help us meet our daily calcium requirements, which range from 500-1300mg depending on our life stage.
Calcium is a mineral required for the healthy development and maintenance of strong bones and teeth, and adequate dietary calcium is a prerequisite for maximising peak bone mass during the first three decades of life.
Aussies aren’t consuming enough!
The recent Australian Health Survey 2011-2012 found the average daily amount of calcium consumed from foods and beverages was below the recommended intake in both males and females. With calcium requirements reaching their peak in post-menopausal females (51-70 years), many people are on the search for alternative sources to obtain this mineral, particularly if they need to avoid dairy due to intolerances or simply a dietary preference.
No need to “cry over spilled milk”, there is some good news; it is possible to obtain calcium from non-dairy sources, including some vegetables, nuts & seeds, as well as seafood. There are a couple of things to consider when relying solely on calcium from non-dairy sources, particularly plant-sources. This is because plants contain certain constituents known as oxalates and phytates which may impede calcium absorption and decrease its bioavailability.
There are also many advantages of obtaining calcium from plant-based foods, as in addition to calcium, these foods are also rich sources of vitamin K, potassium and vitamin C.
- Higher phytate and oxalate foods may have lower absorption rates and include spinach, rhubarb, swiss chard and beet greens. For instance, to obtain the same amount of calcium from a cup of regular milk, you would have to consume over 1kg of spinach.
- Lower phytate and oxalate foods have higher calcium absorption and include kale, broccoli, bok choy, leafy greens and mustard greens.
| Food | Calcium (mg) per serve | Standard serve (g) | Estimated absorbable calcium (mg) | Servings needed to equal 240ml milk |
| Regular milk | 304 | 240 | 96.3 | 1.0 |
| Cheddar cheese | 303 | 42 | 97.2 | 1.0 |
| Yoghurt | 300 | 240 | 96.3 | 1.0 |
| Bok choy | 79 | 85 | 42.5 | 2.3 |
| Broccoli | 35 | 71 | 21.5 | 4.5 |
| Chinese mustard greens | 212 | 85 | 85.3 | 1.1 |
| Kale | 61 | 85 | 30.1 | 3.2 |
| Spinach | 115 | 85 | 5.9 | 16.3 |
| Rhubarb | 174 | 120 | 10.1 | 9.5 |
How do I maximise my calcium intake from non-dairy sources?
- Monitor your intake of sodium, protein and caffeine, as a higher consumption of these can increase calcium losses in the urine.
- Carefully plan your meals, as larger serving sizes may be required.
- Lifestyle factors such as smoking can also increase calcium urinary losses.
- Choose lower phytate and oxalate plant-sources such as kale, broccoli, bok choy, leafy greens, mustard greens and collard.
- Consider calcium fortified non-dairy milks such as soy and almond.
- Go nutty with nuts and seeds, including almonds with the skin and Brazil nuts. Or even try adding unhulled tahini to your food, it contains 66mg calcium per tablespoon.
- Add tofu (make sure it’s firm) to your stir-fries as it contains a whooping 832mg of calcium per cup.
- Seek out seafood! Canned sardines with crushed bones contain 486 mg of calcium and canned pink salmon contains 279mg of calcium per 90mg.
- Although diet should be first and foremost, supplementation with calcium can also help you reach your daily requirements.
If avoiding dairy foods, calcium requirements can be met through non-dairy sources. Although it may be a little more difficult, carefully planning your meals can help to optimise sufficient absorbable dietary calcium to keep your bones happy in the longer term.
