🦴 Calcium

Calcium is a mineral that bones and teeth are largely built from: about 99% of the body's calcium sits there, according to EFSA. The rest is needed by muscles, nerves and blood vessels. The body does not make calcium itself, so it comes from food. Milk is one of the main sources: 100 g of whole milk holds about 119 mg (USDA).

In milk, a large part of the calcium is bound to casein (Tetra Pak). According to FAO, few foods naturally contain as much calcium as milk, and it is well absorbed. Hard cheddar has about 721 mg per 100 g, while cottage cheese has only 83 mg, because its calcium mostly comes from the whey left in the cheese.

On EU labels, the reference value is 800 mg a day. In 2015 EFSA set 950 mg for adults from 25 years and 1000 mg a day for ages 18–24. In 2012 EFSA confirmed the upper limit from food and supplements together: 2500 mg a day for adults.

In the EU, health claims are allowed only for a "source of calcium": at least 15% of 800 mg, or 120 mg per 100 g. It may be said that calcium is needed for normal bones and teeth, muscles, blood clotting, the transmission of nerve signals and the work of digestive enzymes, and that it takes part in cell division.

Calcium is the mineral itself, not a vitamin, and it is not the same as vitamin D: vitamin D only contributes to normal absorption of calcium. About 99% of the body's calcium sits in bones and teeth, and because the body does not make it, it must come from food. Milk is one of the main sources, with about 119 mg per 100 g, and few foods naturally hold as much. Hard cheddar has about 721 mg per 100 g, cottage cheese only 83 mg. For supplements, remember the upper limit of 2500 mg a day from all sources.

On a label, look for “calcium” and the percentage of the NRV (nutrient reference value), which the EU counts from 800 mg. A “source of calcium” claim means at least 120 mg per 100 g. You will see it on cartons of milk, yoghurts and hard cheeses at the supermarket dairy aisle, and on supplement packs at the pharmacy or health-food shop. A glass of milk (250 ml) gives about 300 mg of calcium.

Why it matters to you. On a label, "source of calcium" means at least 120 mg per 100 g, and a glass of milk (250 ml) gives about 300 mg. Vitamin D contributes to normal absorption of calcium (an authorised EU claim); as for supplements, remember the upper limit of 2500 mg a day from all sources.