home Audience 2 The role of sodium in the human body, symptoms of sodium deficiency and excess, which foods contain it. How sodium affects the human body - the consequences of deficiency and excess

The role of sodium in the human body, symptoms of sodium deficiency and excess, which foods contain it. How sodium affects the human body - the consequences of deficiency and excess

Sodium is an element that the body needs for proper operation. Salt contains sodium.

The body uses sodium to control blood pressure and blood volume. Sodium is also necessary for muscles and nerves to function properly.

Food Sources of Sodium

Sodium occurs most naturally in food products. The most common form of sodium is sodium chloride, or " salt" Milk, beets, and celery also contain natural sodium, as does drinking water, although the amount varies depending on the water source.

Sodium is also added to various foods. Some of these additional forms are: MSG, sodium nitrite, sodium saccharin, baking soda (sodium bicarbonate), and sodium benzoate. They are found in items such as soy sauce, onion salt, garlic salt, bouillon cubes, etc.

Processed meats - such as bacon, sausage, ham, and canned soups and vegetables - are examples of foods that contain added sodium in fairly large quantities. Fast foods tend to be very high in sodium.

Daily sodium requirement

Sodium in the diet (called dietary sodium) is measured in milligrams (mg). Table salt contains 40% sodium, and 1 teaspoon of table salt contains 2300 mg of sodium.

Healthy adults should limit their sodium intake to 2,300 mg per day. Adults with high blood pressure should consume no more than 1,500 mg per day through food. People with congestive heart failure, cirrhosis of the liver, and kidney disease may need to reduce the amount of sodium in their diet.

The specific amount of sodium intake that is recommended for infants, children, and adolescents is not clear. Eating habits and attitudes toward food are formed in childhood and likely influence eating habits throughout life. However good idea For health - avoid large amounts of salt in food.

Sodium (Na) ranks eleventh in Periodic table. In the free state, it is a soft (like plasticine) silver-white metal, which very quickly oxidizes in air to form an oxide and, due to the content of water vapor in the air, a hydroxide. Therefore, free sodium is stored under a layer of kerosene.

Its name comes from the Latin natrium, which means “soda”, “caustic soda”. It is no coincidence that before giving it the appropriate official name it was also called "sodium".

IN pure form sodium was obtained in 1807 by electrolysis of sodium hydroxide by the English chemist Humphrey Daphy. Remarkably, in a similar way (by electrolysis of the hydroxide melt) he isolated potassium a few days earlier.

Sodium is very common in nature. In the earth's crust its content is about 25 kg per ton, and in sea water on average 10.5 g/l.

Despite its very high chemical activity, metallic sodium occurs in nature, albeit in small quantities. It is in this state that this metal gives Blue colour rock salt deposits. But if you just dissolve rock salt in water, there will be no trace of free sodium left. Thus, we can say with absolute certainty that at the time the salt deposits were formed, there was no trace of free sodium there. But how did he get there? It was formed there due to the effects of radiation, which destroyed sodium chloride molecules into constituent elements. An effect somewhat similar to the decomposition of silver chloride under the influence of light. By the way, ordinary (chemical) black and white photography was based on this effect.

Currently, sodium metal is produced primarily by electrolysis of sodium hydroxide (NaOH) or sodium chloride (NaCl).

Sodium has many interesting physical and chemical properties. So, it melts at a temperature below the boiling point of water (at normal conditions the melting point of sodium is 98 o C). If you heat it under high pressure, it will become red and transparent like a ruby. Sodium is lighter than water, so if a piece of this metal is thrown into water, it will float (run along the surface of the water), while violently interacting with it to release hydrogen. At the same time, it will also melt, since the reaction is accompanied by the release of heat. If you take a larger piece of sodium (several grams), then upon contact with water, an explosion of released hydrogen may occur.

If you drip stationery glue onto a piece of sodium, then at the very beginning nothing will seem to happen. But after a couple of minutes the sodium will flare up and burn.

The role of sodium in the human body

Once ingested, sodium begins to be rapidly absorbed. This already occurs in the stomach, but the main part is absorbed later, in small intestine.

In the human body, sodium is present in the form of soluble compounds, so it can be found in the blood, lymph, intercellular fluid, and in all tissues and organs. In this case, the main part (half) of sodium falls on the intercellular fluid, another about 40% on the bones and cartilage tissue, and only 10% gets inside the cells.

The importance of sodium in maintaining life cannot be overestimated. Being a potassium antagonist, it ensures normal fluid balance in the body of all living beings. In this case, sodium “works” on fluid retention, potassium on excretion. Sodium is also directly involved in the acid-base balance of the body.

Sodium ions Na + regulate the excitability reactions of neurons, and thereby ensure the conduction of nerve impulses. It is no coincidence that when there is a lack of sodium, it is found muscle weakness, apathy and drowsiness.

Entering the body in the form of chloride (table salt), sodium ensures the synthesis of hydrochloric acid, which is necessary for the breakdown of proteins in the stomach, and activates the activity of many digestive enzymes.

Sodium also enhances the effect of adrenaline, so its excess contributes to a slight increase in a person’s aggressiveness.

Sources of sodium

The main source of sodium for the human body is table salt. Daily dose sodium is contained in just one teaspoon (5-6 g) of this most common seasoning. IN in this regard humans, unlike other animals, are very lucky, since animals get sodium from food, and very often feel a lack of this essential mineral element. Therefore, sometimes people specifically feed domestic and wild animals (for example, moose) with salt. However, a person’s luck here is very conditional, since people suffer from the opposite misfortune - an excess of sodium. It is no coincidence that so-called salt-free diets have recently become popular in the world. Replenishing your body with sodium without table salt is quite easy. To do this, you need to include in your diet:

At the same time, some foods are so high in salt that they need to be consumed in limited quantities to prevent excess sodium. This:

ham, carbonates, boiled pork, sausages and generally all sausages;
brines;
sauces (mayonnaise, ketchup, soy sauce);
canned and pickled vegetables (cucumbers, tomatoes, zucchini, etc.);
cheese (especially processed cheese);
salted nuts and crackers, chips, dried fish and salted fish;
soda and products containing it (muffins, cookies, etc. with shortcrust pastry).

Lack (deficiency) of sodium

Sodium deficiency is rare these days. However, due to their occupation, some people lose so much sodium through sweat and urine that they need to increase their intake. This applies to athletes, people working in a hot shop, in a hot climate under the scorching sun, etc. In extreme cases, they require up to 20 g of sodium per day, which is contained in 45 g of table salt. However, in order to remove this amount of salt from the body, they have to consume a lot of water.

Sodium retains water, thereby saving the body from dehydration. It is no coincidence that the Bedouins living in the deserts, when traveling long distances in the hot season (in caravans), take salt tablets. Thus, they significantly save space for other luggage (instead of water).

Sodium deficiency can occur in a number of diseases gastrointestinal tract, cholera, food poisoning due to vomiting and diarrhea, leading to dehydration, as well as abuse of diuretics and laxatives.

In some people, with the accumulation of fluid in the body associated with kidney and heart diseases, so-called hyponatremia may occur, when the amount of sodium in the body is sufficient, but due to its low concentration in the body, metabolism, acid-base and electrolyte balance are disrupted. In this case, additional sodium intake only worsens the problem, because it helps retain fluid in the body. The only way out is in complex treatment disease that caused the swelling.

If a person is on a salt-free diet for too long, receiving less than 0.5 g of sodium per day, he may experience the following: symptoms of sodium deficiency:

dry skin, impaired elasticity and firmness;
leg cramps;
thirst;
nausea and vomiting;
decline blood pressure(hypotension);
weakness and chills;
drowsiness and apathy, depression, confusion, causeless anxiety, fatigue, hallucinations;
weakening of memory, mood swings;
imbalance when walking, dizziness;
decreased urine output;
loss of sense of taste and appetite;
muscle wasting;
body weight deficiency;
susceptibility to infectious diseases.

Short-term sodium deficiency does not cause harm to the body serious consequences. However, prolonged shortage leads to its leaching from bone tissue, which leads to its destruction. Long lasting as well as fast and sudden loss sodium in the body can lead to increased breakdown of proteins, a decrease in osmotic pressure in tissues, an increase in residual nitrogen and the development of persistent depression. All these symptoms are well known to people who have had long fasts on the water (see article “Fasting is harmful”). If in such a state a person is given a glucose solution, a hypotonic solution, or just given a large amount of water to drink, this can lead to a coma, even death.

Excess sodium

If you eat a lot of salty foods, excess sodium is almost guaranteed. To determine excess sodium, it is enough to perform one simple test on yourself: weigh yourself, spend 3 days on a salt-free diet and... weigh yourself again. If you suddenly find that you have “lost” more than 1 kg (assuming you have maintained your normal diet and lifestyle all this time), then you have excess sodium. In the future, try to adhere to salt intake standards. If you are a “salty” lover, you can instead regular salt use sea. Firstly, it has a stronger taste, and therefore you will need half as much of it, and secondly, it contains salts of other metals, which, being sodium antagonists (primarily potassium), will remove excess sodium from the body.

Symptoms of excess sodium:

violation water-salt metabolism, swelling;
thirst;
dysfunction of the adrenal glands and kidneys;;
diabetes;
hypertension;
hyperactivity and excitability.

To withdraw extra salt from the body, you need to consume a sufficient amount of clean drinking water Calculation: 1 liter of water removes 1 g of salt from the body.

Excess sodium is a serious problem. Its consequences occur unnoticed at first, but are irreversible. Edema, many diseases of cardio-vascular system(eg hypertension), kidney and liver develop due to overconsumption salt.

Lack of sodium in the body

The role of sodium in the body

The substance is found in human cartilage and bone tissue (in percentage) – up to 40%; in blood, plasma and lymph – up to 50%; in cells – less than 10%.

Sodium plays important role in metabolism and regulates:

Sodium in the body creates a special environment that is required for the formation muscle tissue. The macroelement is involved in the transport of carbon dioxide and improves the digestibility of proteins.

The main supplier of sodium to the body is salt. Approximately 15 grams of table salt contains from 4 to 6 g - daily norm sodium for an adult. In case of excessive sweating, heavy physical exertion, or poisoning, the consumption rate increases.

What are the dangers of lack of sodium in the body?

Macronutrient deficiency occurs due to excess excretion through excretory system, skin, eating foods with insufficient salt content, dehydration. Another factor that provokes a decrease in sodium is the presence of gastrointestinal diseases.

A deficiency of the mineral causes the following symptoms:

dry skin, decreased elasticity;
syndrome restless legs, frequent night cramps;
unquenchable thirst;
causeless vomiting;
decreased blood pressure;
decreased frequency of fluid excretion from the body (rare urination);
lethargy, fatigue, apathy;
dizziness, memory loss, loss of consciousness, depression.

A sharp loss of sodium by the body with simultaneous use large quantity liquid or intravenous administration glucose can cause death.

Eating helps compensate for the loss of macronutrients fresh vegetables, fruits, berries, onions, cereals and legumes.

To reduce the likelihood of loss normal level sodium in the body, it is recommended to abandon salt-free diets and the use of diuretics (strong coffee, tea with a diuretic effect).

Sodium has been known since ancient times among different peoples. It was extracted in the form of alkali from soda lakes, which was used for washing, making glazes for dishes and even in the mummification of corpses. This element had several names - nitron, neter. In the Middle Ages, they did not make much of a distinction between potassium and sodium; they referred to alkalis for making saltpeter. And only in the 18th century the scientist Klaproth divided them into vegetable alkali (potash) and mineral alkali (soda or natron). But another scientist from England received them in free form and called them potassium (Potassium or potassium) and sodium (Sodium or sodium).

Sodium is so highly active that it is very difficult to obtain in free form. It is silver in color (see photo), melts very easily (at 98 degrees Celsius) and is so soft that it can be cut with a knife. It does not dissolve in water and does not sink; it floats on its surface. In nature, it is found in many substances, it is contained in all bodies of water and in table salt - this metal is the sixth most abundant on the planet.

In the human body, many processes could not occur in the absence of this trace element. Sodium is present in the blood, lymph, and digestive juice in the form of salts - chlorides, phosphates and bicarbonates.

The action of sodium, its role in the human body and functions

The effect of a microelement on the human body is determined by its distribution in all tissues and fluids of the body, without exception, and therefore, along with potassium, it is one of the most in demand and plays an important role in the body.

This substance takes an active part in metabolic processes in cells and between them, normalizes osmotic pressure, being a positively charged ion. In addition, it regulates the excitability of the nervous and muscle fibers thanks to the interaction of potassium, sodium and chlorine, it normalizes the acid-base balance, has positive impact for the production of digestive enzymes and is a conductor of glucose. It enhances the effect of adrenaline, which has a positive effect on the arteries and promotes their narrowing.

Sodium compounds also have this function: they are able to retain water in the body, avoiding its unnecessary loss, but at the same time, in combination with potassium, it prevents the retention of excess water.

Most of the sodium that enters the body is absorbed in the small intestine, and only a small amount is absorbed in the stomach. About 10% enters the cells themselves, and about half of all sodium is distributed in the pericellular fluid. The rest is concentrated in bones and cartilage tissue.

Daily norm - what is the need for the human body?

The body's daily requirement for macronutrients can mainly be covered by consuming the main source - table salt. One teaspoon contains 2 grams of sodium.

An adult needs about 2 grams of sodium per day, but a child needs to consume 2-3 times less, depending on age.

It is also necessary to take into account that with active sweating and diuresis, sodium is very actively washed out. Therefore, the need may increase to 6 grams. The maximum amount of salt that our kidneys can process without much harm is within 20 grams. large quantity may pose a danger to life.

There is an approximate calculation of sodium intake for a person: for 1 liter of water drunk per day, you need to consume 1 gram of table salt.

Our body cannot produce this element on its own, so it can only come from external sources. As is already known, a person receives the bulk of sodium from table salt. Sea salt has beneficial features only in purified form.

This is present chemical element in hard cheeses, milk, beef, seaweed and seafood, carrots, beets and mineral water. There is also a large amount of sodium found in bakery products And finished products– sauces, seasonings, canned food, soy sauce.

In addition to the beneficial sodium in the composition ready food, there is a large amount of monosodium glutamate, called the “soul of taste”. And in this form it can be considered a slow-acting poison. He can even turn cardboard into a very appetizing dish. Although according to the official version, such a taste enhancer is absolutely harmless, in fact, already in 1957, scientists identified its toxic effect, leading to impaired vision, obesity and multiple sclerosis.

Lack (deficiency) of sodium in the body

Macronutrient deficiency is quite rare and occurs as a result of strict diets or fasting, as well as with frequent uncontrolled use of diuretics, potassium and calcium, and with diseases of the kidneys and adrenal glands.

Lack of sodium can cause weakness, increased fatigue, dizziness, convulsions, skin rashes and hair loss. Impaired absorption of carbohydrates may develop. Processes such as decreased blood pressure and low urination also occur, attacks of thirst, nausea, and vomiting appear.

Regular deficiency of the substance can cause hallucinations, impaired consciousness and vestibular apparatus. If left untreated, proteins are broken down and the amount of nitrogen in the body increases. In such cases, administering glucose or large amounts of water can be fatal.

Vitamin D promotes the absorption of sodium, but this effect can be neutralized by too salty foods, which are also rich in proteins.

Excess sodium - what are the symptoms?

Excess sodium in the human body occurs much more often than deficiency and can cause significant harm.

It is difficult to find a person who does not consume salt in food several times a day, so most often the amount of salt even exceeds the necessary norm. In addition, excess sodium can cause diseases such as hypertension, neuroses, diabetes, and kidney dysfunction. And salt additionally increases the load on the kidneys and heart, inhibits the movement of blood, because sodium chloride begins to displace important substances from cells. Therefore, it is important to promptly remove excess sodium by eating fermented milk products.

Overdose causes the following symptoms: heavy sweating, increased urination, thirst, overexcitement and hyperactivity. Fluid accumulates in the body, swelling appears and hypertension occurs.

Indications for use

Indications for microelement administration:

IN human body about 100 g of sodium is concentrated. 30-40% of this mineral is found in bones and cartilage. 50% contain intercellular fluids. The cage contains the remaining 10%.

Sodium in the human body maintains water-salt balance and regulates neuromuscular activity. Thanks to it, all substances in the blood are maintained in a soluble state. Responsible for the delivery of various substances to organs and is involved in muscle contractions.

Sodium is absorbed into the human body by almost 100%. It can be absorbed through the pulmonary epithelium and skin. Absorbed thanks to vitamin K and vitamin D.

Let's take a closer look at the functions of sodium in the human body.

The role of sodium in the human body

When interacting with chlorine, it helps retain liquid in blood vessels and prevents it from penetrating into nearby tissues.
transports blood sugar to all cells of the organ;
takes part in muscle contraction;
promotes vasodilation;
transports various substances across cell membranes nutrients, for example, amino acids, glucose, various inorganic and organic anions through cell membranes.
transports carbon dioxide;
influences protein metabolism in the body;
participates in synthesis gastric juice;
regulates the excretion of various metabolic products in the kidneys;
stimulates the production of pancreatic enzymes and salivary glands,

Symptoms of sodium deficiency

Signs of a mild sodium deficiency

Severe symptoms of sodium deficiency

Why might the body lack sodium?

Lower sodium levels may help

diarrhea;
vomit;
heart failure;
kidney and liver diseases;
use of certain medications;
drinking a lot of water;
drug use;
hormone dysfunction thyroid gland;
intensive physical exercise;
very hot weather;
insufficient food intake;
traumatic brain injuries;
excess and potassium;
prolonged contact with sea water;
lack of chlorine and vitamin D in the body.

Excess sodium in the body

Excess sodium is also undesirable for the body. The kidneys especially suffer from this, since they have to remove its excess content.

At large doses sodium, fluid accumulates in the body, causing swelling in the muscles. It also increases blood pressure, and the heart suffers accordingly. Moreover, sodium displaces such no less useful minerals, like potassium, calcium, magnesium.

How much sodium does the body need?

According to a study by the World Health Organization (WHO), the level of sodium consumption in the world is significantly higher than human biological needs. Therefore, the recommended daily intake for adults should be 2 g sodium per day (5 g salt).

For athletes and people whose activities are related to physical activity, this dose can be increased to 3 grams. Children should not consume more than 0.3 g per day.

What foods contain sodium?

The main source of sodium is, of course, table salt. 100 g of salt contains approximately 40 g of sodium. A tablespoon of salt contains about 2 g of this element.

Quite a lot of sodium in foods such as sea salt, soy sauce, brine, sauerkraut.

Slightly less of this mineral in rye bread, hard cheese, milk, chicken eggs, beef.

There is some sodium in seaweed, crabs, carrots, beets, chicory, and celery.