Calcium is an alkaline earth metal is chemically related to magnesium.

The adult human body contains 1 000 to 1 200 g of calcium which approximately 99% are located in the bone as hydroxyapatite calcium phospate crystallized and amorphous provide rigidity, strength and hardness of skeleton teeth.

Bone is a living organ, constantly renewed and serves as a reserve of exchangeable calcium, available for soft tissue. The low proportion (1%) of extra-osseous body calcium is just as important as the large pool and skeletal occurs, its free ionized fraction in multiple functions: excitability, membrane permeability, release of hormones, activation enzimes, ...

Sources of Calcium

See the list of foods that provide the most calcium


In adults, calcium absorbed (about 300 mg per day) is practically not retained in bone and is excreted in equal shares presques the endogenous fecal and urinary tract, and to a lesser extent in sweat.

Coefficiant to reflect actual absorption of ingested calcium, and nutritional means, the value of 100% ANC Nutritiomètre ® for adults is 900 mg.

Excess dietary calcium can inhibit the intestinal absorption of other elements such as magnesium and especially iron. It therefore seems prudent to maintain the safety limit toxicity 2 g of calcium per day (almost 200% on Nutritiomètre ®).

Even if there is no recommendation on the lower limit, it seems that we should not fall below 60% of the value of ANC Nutritiomètre ®.

(Source: "Recommended dietary allowances for the French population," the CNERNA-CNRS. Edition coordinated by Ambroise Martin.)