Calcium
Ca · last AI check: 2026-07-19
In short
The main building block of bones and teeth. Well absorbed from dairy and fortified products.
What it does in the body
The sentences below are officially authorised EU health claims.
Calcium is needed for the maintenance of normal bones EU health claim
Commission Regulation (EU) No 432/2012 of 16 May 2012, Annex — list of permitted health claims · register entry: 224, 230, 350 · EFSA opinion: 2009;7(9):1210; 2009;7(9):1272; 2010;8(10):1725; 2011;9(6):2203
Condition of use on a product: The product is at least a source of Calcium.
How much you need
| Country / organisation | Group | Value | Type |
|---|---|---|---|
| EFSA | adults 25+ | PRI Population reference intake — the EFSA (EU) equivalent of the RDA. | |
| FAO | adult men | RNI Reference nutrient intake — the RDA equivalent in WHO/FAO, UK and Philippine terminology. | |
| Philippines | adults | RNI Reference nutrient intake — the RDA equivalent in WHO/FAO, UK and Philippine terminology. | |
| India | adult men | RDA Recommended daily allowance — covers the needs of almost all healthy people in a group. | |
| Japan | adults | — A value not tied to one jurisdiction — an indicative compilation from several sources. | |
| Singapore | adults | RDA Recommended daily allowance — covers the needs of almost all healthy people in a group. | |
| Switzerland | adult men | RDA Recommended daily allowance — covers the needs of almost all healthy people in a group. | |
| United Kingdom | adults | RNI Reference nutrient intake — the RDA equivalent in WHO/FAO, UK and Philippine terminology. |
Reference values from different countries are not directly comparable — they differ in definition and age group. How to read reference values →
Every value states its source — click it to see the document, location and link.Data and content are prepared and cross-checked against source documents by several independent AI models. They have not been audited by a human editor.Before citing a value, check it in the source document — verification is automated (AI), not editorial.
Worth knowing
Calcium is the most abundant mineral in the body — the great majority of its stores are found in bones and teeth, where it forms hydroxyapatite together with phosphorus. The rest, although only a fraction of the total, is responsible for functions the body couldn't survive a moment without: nerve conduction, muscle contraction and blood clotting.
Bone as a store, not just a scaffold
This division of roles explains something that can be confusing. Blood calcium concentration is kept within a very narrow range regardless of how much we eat — when intake is low, the body tops up the blood level by drawing on bone. So a normal serum calcium result says nothing about whether the diet is providing enough, and bone status is assessed by other methods. Interpreting these tests is for a doctor.
Absorption depends on vitamin D and on what we eat alongside it
Absorbing calcium requires vitamin D — their authorised health claims can be found on this page and on the vitamin D page. Absorption is limited, on the other hand, by oxalates, present in large amounts in spinach and rhubarb, among others. This is why spinach, despite its high calcium content in composition tables, is a poor source of it in practice — while cabbage, kale or broccoli are considerably better sources, despite lower figures.
For people who don't eat dairy, the most predictable source is plant-based drinks fortified with calcium — provided they really are fortified, since unfortified versions contain only trace amounts. It's worth checking the label, and also shaking the carton: added calcium is sometimes insoluble and settles at the bottom.
Where to find it
dairy products · fortified plant-based drinks · green vegetables · tofu
This material is for information and education. It does not replace advice from a doctor or dietitian. For health matters, consult a qualified medical professional.