Key takeaways
- Calcium is the most abundant mineral in the body — 99% is stored in bones and teeth
- The recommended daily intake for adults is around 950–1,000 mg
- Dairy is not the only source: tahini, sardines, kale, almonds and fortified plant milks are all strong alternatives
- Vitamin D is essential for calcium absorption — without it, high intake makes little difference
What does calcium do in your body?
Calcium is primarily known for building and maintaining bones and teeth. But it also plays essential roles in:
- Muscle contraction — including the heart muscle
- Nerve signalling — transmitting impulses between nerve cells
- Blood clotting — calcium is involved in several clotting factors
- Hormone release — calcium triggers the release of hormones and enzymes
When dietary calcium intake is too low, the body draws calcium from bones, which over time contributes to osteoporosis.
How much calcium do you need per day?
| Group | Daily recommendation |
|---|---|
| Children (4–8 years) | 800 mg |
| Adolescents (9–18 years) | 1,200 mg |
| Adults (19–50 years) | 950 mg |
| Adults (50+ years) | 1,000 mg |
| Pregnant and breastfeeding women | 950 mg |
Source: Dutch Health Council
Calcium sources beyond dairy
Vegetables and legumes
| Food | Calcium per 100 g |
|---|---|
| Tahini (sesame paste) | 426 mg |
| White beans (cooked) | 130 mg |
| Kale | 135 mg |
| Bok choy | 105 mg |
| Broccoli | 47 mg |
Fish and seafood
| Food | Calcium per 100 g |
|---|---|
| Sardines (with bones) | 382 mg |
| Canned salmon (with bones) | 232 mg |
Nuts and seeds
| Food | Calcium per 100 g |
|---|---|
| Sesame seeds | 975 mg |
| Chia seeds | 631 mg |
| Almonds | 264 mg |
Fortified foods
Plant milks (oat, almond, soy) are commonly fortified to contain around 120 mg of calcium per 100 ml — comparable to cow's milk.
Dairy as a calcium source
For completeness, dairy remains one of the most efficient sources:
| Product | Calcium per 100 g/ml |
|---|---|
| Parmesan cheese | 1,109 mg |
| Edam cheese | 740 mg |
| Whole milk | 119 mg |
| Plain yoghurt | 121 mg |
How to improve calcium absorption
Not all dietary calcium is absorbed equally. Key factors:
Enhancing absorption
- Vitamin D — essential for intestinal calcium absorption. Without adequate vitamin D, dietary calcium has limited effect. See our article on vitamin D deficiency
- Lactose — mildly promotes absorption from dairy
- Acidic stomach environment — calcium is better absorbed in an acidic setting
Inhibiting absorption
- Oxalic acid — present in spinach and rhubarb; binds calcium and significantly reduces uptake
- Phytic acid — in wholegrains and legumes (soaking or fermenting reduces this)
- High sodium intake — increases urinary calcium excretion
- Excessive caffeine — mildly increases excretion at very high intakes
Calcium supplementation: yes or no?
For most people eating a varied diet, supplementation is not necessary. It may be considered for:
- People with lactose intolerance or milk allergy without adequate alternatives
- Postmenopausal women (increased osteoporosis risk)
- Those following a long-term vegan diet with consistently low intake
Note: large single doses of supplemental calcium (above 500 mg) are absorbed less efficiently. Spread intake across the day. EFSA has set a tolerable upper intake level of 2,500 mg per day total (food and supplements combined) for adults.
Tracking calcium intake
With Moveno, you photograph your meal and instantly see the mineral breakdown, including calcium — no manual calculation needed.
Conclusion
Calcium is essential, but you do not need to rely on dairy to meet your daily needs. Tahini, kale, sardines, almonds and fortified plant milks are all excellent alternatives. And remember: vitamin D is the key that unlocks calcium absorption. Without enough of it, even a high-calcium diet may not be enough.
Sources: Dutch Health Council (2018); EFSA Panel on Dietetic Products, Nutrition and Allergies (2015); Weaver CM., Advances in Nutrition (2014)
