Calcium: Effects, Daily Requirement & Sources

An adult carries around roughly one kilogram of calcium – no other mineral occurs in the body in this quantity. Most of it is stored in the bones and teeth, which are far more than a rigid framework: they are a living calcium reservoir from which the body constantly deposits and withdraws. It is no surprise that most people immediately think of bones when they hear the word “calcium”.

In short and to the point: calcium contributes to the maintenance of normal bones and teeth and is also important for muscles, nerves and blood clotting. For adults, the requirement is around 1,000 mg per day. Besides dairy products, green vegetables, nuts, seeds and calcium-rich mineral water provide good amounts – for the bones, the interplay with vitamin D and K2 is what counts.

The key points at a glance

• Calcium contributes to the maintenance of normal bones and teeth.
• It also supports normal muscle function, the transmission of nerve signals and blood clotting.
• The requirement is around 1,000 mg per day, with a tolerable total intake of about 2,500 mg.
• For the bones, the interplay with vitamin D and K2 is what counts.
• Not just milk: green vegetables, nuts, seeds and mineral water also provide calcium.

What calcium does in the body – the mechanism

Around 99 percent of calcium is stored in the bones and teeth, where it gives the tissue hardness and stability. But the fascinating part is the one remaining percent in the blood and the cells: it controls highly sensitive processes. For a muscle to contract, calcium flows into the muscle cell. For a nerve to pass on an impulse, calcium signals are involved. And without calcium, blood clotting does not work either. Because this one percent is so decisive, the body keeps the calcium level in the blood meticulously constant – if necessary by mobilising calcium from the bone reservoir. This is precisely why a good intake is also relevant for the bone substance.

Among the approved statements are that calcium contributes to the maintenance of normal bones and teeth, to normal muscle function, to the normal transmission of signals between nerve cells and to normal blood clotting. These statements apply when intake is sufficient and are not a promise of healing.

How much calcium per day?

The DGE recommends around 1,000 mg per day for adults. This amount can often be reached well with a balanced diet – those who regularly eat dairy products are usually well supplied. About 2,500 mg per day from all sources combined is considered the tolerable total intake. This value indicates that more is simply not better.

Sources: far from just milk

Milk is regarded as the calcium classic – rightly so, but it is by no means the only good source. Anyone who does not eat dairy products has plenty of alternatives:

Especially for people following a vegan or lactose-free diet, this range is good news – more on this in Nutrients for Vegans and Nutrients with Lactose Intolerance. An often underestimated tip: calcium-rich mineral water adds up noticeably over the course of the day.

The right partners

Calcium does not act alone: vitamin D contributes to the normal absorption and utilisation of calcium and promotes uptake from the intestine. Vitamin K2 also plays a role when it comes to bones, and magnesium is the counterpart in the balance. More on this in Vitamin D, Vitamin D and K2 Together and Combining Supplements Correctly. How to take calcium in practice is explained in Calcium: When and How to Take It.

What research is investigating

The role of calcium for bones, teeth, muscles and nerve conduction is established textbook knowledge. Beyond that, research is investigating how the calcium requirement changes over the phases of life, what role the interplay with vitamin D, K2 and magnesium plays for bone metabolism, and how calcium from foods differs from high-dose supplements. Interesting: calcium from food is generally considered less problematic than very high supplement amounts – an argument for looking at the plate first.

Calcium in different phases of life

The requirement remains relevant throughout life, but the emphasis shifts. During growth, bone mass is built up; in middle age it is maintained; and over the years, preserving the bone substance comes more strongly into focus – see Vital Nutrients from 50 and Nutrients for the Bones. During pregnancy and breastfeeding, separate recommendations apply; here it is worth seeking medical advice.

Put honestly into perspective

The fundamental role of calcium for bones, muscles and nerves is well established – that is undisputed. Open and individual is the question of whether you even need to supplement: many people meet their requirement through their diet. So check your meal plan first before reaching for a supplement. If you have existing conditions, are pregnant or are taking medication, clarify the intake with a doctor. This article provides general information and does not replace medical advice.

Matching products from Scheunengut

You will find calcium products in the Calcium category, and suitable partners in the Vitamin D and Magnesium categories. Anyone thinking more broadly will also find something in the Minerals category. All products are laboratory-tested and made in Germany.

Frequently asked questions (FAQ)

How much calcium do you need per day?

The DGE recommends around 1,000 mg per day for adults. This amount can often be reached well with a balanced diet. About 2,500 mg per day is considered the tolerable total intake from all sources – more is not better.

Is milk the only good source of calcium?

No. Besides dairy products, green vegetables such as broccoli and kale, sesame, almonds and hazelnuts, fortified plant-based drinks and calcium-rich mineral water (over 150 mg per litre) provide good amounts. This means vegan and lactose-free diets can also be well covered.

Why does calcium need vitamin D and K2?

Vitamin D contributes to the normal absorption and utilisation of calcium and promotes uptake from the intestine. Vitamin K2 plays a role when it comes to bones. The interplay of these nutrients is more relevant for the bones than calcium alone.

Does everyone need to supplement calcium?

No. Many people meet their calcium requirement through a balanced diet. First check your meal plan with dairy products, green vegetables, nuts and mineral water. Whether supplementation makes sense depends on your individual supply – when in doubt, clarify with a doctor.