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Calcium
Medical expert of the article
Last reviewed: 05.07.2025
Calcium (Ca) plays an important role in blood clotting and is also part of bones and teeth. Only calcium affects the strength of bones and is deposited in our body throughout life. What other useful functions does calcium perform, we will now find out.
[ General characteristics of calcium
The amount of calcium in our body is very easy to calculate. It will be about 2% of the total body weight, that is, approximately 1000 - 1500 g. About 99% of it is part of the bones, dentin and enamel on the teeth, and the rest is part of the nerve cells and soft tissues.
Amount of calcium needed per day
A person needs 800-1000 mg of calcium per day. If you are over 60 or an athlete, then increase this amount to 1200 mg.
Under what conditions does the need for calcium increase?
It is known to all that children from an early age need to be given a lot of cottage cheese and other dairy products, and all because at an early age the need for calcium is very high. If a child receives enough of this element in childhood, he will be healthy and will not have problems with bones.
Pregnant women and women who are breastfeeding should also eat a lot of calcium-rich foods. The health of the future or existing child depends on it!
Doctors also recommend that athletes and people who sweat heavily increase their daily calcium intake.
The beneficial effects of calcium on the body
Calcium is the material for the structure of teeth and bones. Blood cannot exist without calcium, because it is part of it. Tissue and cellular fluid also contain calcium. Calcium prevents viruses and foreign bodies from entering the body, and plays an important role in blood clotting.
Calcium is involved in the management of hormone functions, is responsible for the secretion of insulin, exhibits anti-allergenic and anti-inflammatory properties in the body, is involved in the synthesis of nucleic acids and proteins in muscles, increases the body's defenses, and is involved in the restoration of the body's salt-water balance.
The alkalizing effect in the acid-base balance also occurs with the participation of calcium. Calcium must be present in the body in the required amount to transmit nerve impulses, maintain the work of the heart, muscle contractions, and regulate the stability of the nervous system. Calcium is stored in long tubular bones.
What is interesting is that when the body is poorly supplied with calcium, it itself uses the stored calcium for the "needs" of the blood. With the help of the parathyroid hormone, phosphorus and calcium are transferred from bone tissue to the blood. This is how bones are sacrificed for the well-being of the blood!
Calcium absorption by the body
Calcium is a difficult-to-digest element, so it is not easy to provide the body with the required amount of calcium. For example, cereals, sorrel and spinach contain specific substances that prevent the absorption of calcium. In order for calcium to be absorbed, it is first processed by hydrochloric acid in the stomach, and then exposed to bile so that calcium salts can turn into digestible substances.
In order not to reduce the absorption of calcium, you should not simultaneously consume sweets and saturated carbohydrates, as they cause the release of alkaline gastric juices, which prevent hydrochloric acid from processing calcium.
On the other hand, excess magnesium (Mg) and phosphorus (P) in the body prevents the processing of calcium. The fact is that phosphorus (P) enters into a chemical reaction with calcium and forms a salt that cannot be dissolved even in acid.
Calcium is well absorbed from dairy products, as they contain lactose - milk sugar. Under the influence of intestinal microflora, it turns into lactic acid and dissolves calcium. Any amino acids or even citric acid form substances together with calcium that dissolve easily.
Fats also help calcium to be absorbed well. But there should be a certain amount of them. If there is not enough fat, there will not be enough fatty acids to process calcium, and if there is too much fat, there will not be enough bile acids. The calcium to fat ratio should be 1:100. So, cream with 10% fat content, for example, will suit you.
Interestingly, pregnant women absorb calcium much better than those who are not expecting a child.
Signs of calcium deficiency in the body
When there is a lack of calcium, people experience growth retardation and increased nervous excitability. Such people suffer from insomnia, numbness and tingling in the limbs, joint pain and brittle nails. They have high blood pressure, an increased pain threshold, and a rapid heartbeat. One of the signs of calcium deficiency is a craving for eating chalk.
Women with a calcium deficiency experience frequent, heavy menstruation.
Children with a calcium deficiency may develop rickets, and adults may develop brittle bones and osteoporosis. With a low amount of calcium in the blood, muscle contractility may be impaired: cramps and convulsions occur.
People with insufficient calcium levels may experience a sharp decline in mood. Such a person becomes nervous, may feel nauseous, and may lose appetite.
Signs of calcium excess
Excess calcium can occur when taking too much calcium at the same time as vitamin D. It can also occur if a person eats only dairy products for a long time. Excess calcium can settle in organs, muscles and on the walls of blood vessels. When calcium and vitamin D are introduced into the blood in excess, severe relaxation of muscle tissue can occur. A person can fall into a coma or lethargic sleep.
What influences the calcium content of foods?
A significant amount of calcium can be lost during the preparation of cottage cheese, so it is often specially enriched with calcium.
Causes of Calcium Deficiency
If the stomach lacks lactose, an enzyme that processes milk, calcium absorption may be impaired. 10 days before menstruation, women experience a sharp drop in calcium levels. During menstruation, this leads to contractions of the uterus, which causes painful sensations. When eating exclusively plant foods, vitamin D practically does not enter the body, which reduces calcium absorption.
Products containing calcium
All dairy products contain calcium. Some more, some less. Cheeses can contain up to 1000 mg of calcium. Thus, processed cheeses contain 860-1006 mg of calcium, cottage cheese - 164 mg, feta cheese - 630 mg. Sour cream is very useful for the body, because it contains 90-120 mg of calcium, and our favorite whipped cream - 86 mg. Various nuts can contain from 100 to 250 mg of calcium, so lovers of "nuts with beer" will not suffer from brittle bones.
Regular oatmeal contains up to 170 mg of calcium, and if you eat it every morning, then together with other products it will completely provide your body with calcium.
Interaction of calcium with other elements
When taking medications such as calcium carbonate with food, the absorption of iron sulfate is disrupted. If you take calcium carbonate even in large quantities on an empty stomach, the iron (Fe) will be absorbed perfectly. Good absorption of calcium is facilitated by taking vitamin D.