1. The chemical name of table salt is NaCl.

In the famous painting "The Last Supper", the famous painter Leonardo da Vinci painted an overturned salt shaker in front of Judas who betrayed Jesus.

The purpose of this painting is to metaphorize the evil of Judah.

In ancient times, salt had a very high status. If the salt shaker was knocked over during meals, it was regarded as a bad omen or evil.

It makes sense that humans attach so much importance to salt.

Because salt is an essential substance to maintain normal physiological functions of the human body and maintain health.

The sodium ions and chloride ions in table salt are important substances for maintaining the water balance between cells and the acid-base balance in the blood.

Sodium ions can coordinate blood pressure and blood volume, and can also promote the conduction of nerve impulses.

In addition, the contraction of the heart and muscles cannot be separated from salt.

Experts believe that the average person needs about 4-10 grams of salt every day, of which daily food itself contains 1-2 grams, and the rest of the salt must be added during cooking.

Patients with nephritis, hepatitis, and heart disease should appropriately control their daily salt intake according to medical advice, and patients with hypertension should also appropriately reduce their salt intake.

Long-term excessive intake of salt is the cause of high blood pressure, kidney disease, and heart disease. The incidence of arteriosclerosis is also directly proportional to the amount of salt intake.

In addition to being edible, table salt is also an important industrial raw material and can be used to make soda ash, caustic soda, hydrochloric acid, polyvinyl chloride, etc.

Metal sodium can be produced by electrolysis of molten sodium chloride.

In agriculture, salt solution is used to select seeds to ensure a high germination rate.

Sanitation workers in the city sprinkle salt water to melt snow on the roads to ensure the safety of vehicles and pedestrians.

In the hospital, saline water can be used instead of disinfectant to clean wounds.

In daily life, fish is marinated with salt to preserve it for a long time.

Salt is extremely abundant in nature.

The vast sea is the home of salt.

If all the salt in seawater was extracted and spread on the surface of the earth, a large "salt blanket" about 40 meters thick would be formed to cover the earth.

Currently, the world produces about 100 million tons of sea salt every year. At this amount, salt can be used by humans for 500 million years.

2. Sugar. Sugar generally includes brown sugar, white sugar, rock sugar, etc.

Brown sugar is a mixture of sucrose and molasses, and white sugar is made from brown sugar through several processes such as washing, centrifugation, honey separation, and stripping.

Rock sugar is formed by recrystallization of white sugar under certain conditions.

Their chemical composition is sucrose.

During long-term storage of brown sugar, the molasses will oxidize, resulting in a darker color and a sour taste. At this time, the brown sugar can no longer be eaten.

The function of sugar in the body is only to supplement energy, or to be stored in the body as glycogen. It has a simple function and basically does not contain other nutrients.

Many studies at home and abroad have shown that eating too much sugar or eating it improperly often leads to myopia, dental caries, diabetes, obesity, fractures and other diseases.

In fact, if you don’t eat sugar, your body will not be short of sugar, because sugar is contained in the rice, noodles, fruits, and vegetables we eat every day.

According to nutrition experts’ regulations, children’s daily sugar intake should not exceed 0.5 grams of white sugar per kilogram of body weight, and adults’ daily sugar intake should not exceed 0.55 grams of white sugar per kilogram of body weight.

For this reason, the World Health Organization proposes: For your health, please eat less sugar.

3. MSG One day in 1908, when Japanese chemist Ikeda was drinking kelp and cucumber soup, he felt that it tasted particularly delicious.

This aroused his professional sensitivity, but he conducted a chemical analysis of the kelp and obtained an extraordinary chemical substance-monosodium glutamate.

The business-minded Japanese quickly turned this invention into a commercial product and named it "Ajinomoto". From then on, MSG quickly became popular all over the world.

Some people think that eating too much MSG will cause poisoning, but this has no scientific basis.

On the contrary, the umami flavor of eating MSG can stimulate taste cells and excite digestive glands, increase appetite and promote digestion.

MSG also has certain medicinal value. It can change the nutritional status of the human body and increase acetylcholine in the brain, which can treat neurasthenia. Regular consumption of MSG in moderation can improve children's developmental dysplasia. MSG is related to ammonia in the blood.

The glutathione formed by the combination has a good effect on the treatment of hepatic coma and epilepsy caused by increased blood ammonia.

However, when using MSG, special attention should be paid to the temperature. If it is heated above 120°C during cooking, sodium glutamate will undergo chemical changes and turn into sodium pyroglutamate. Not only will the flavor be reduced, but it will also be slightly toxic.

When making soup, MSG should be added just before it comes out of the pot.

The dosage of MSG should be appropriate, generally no more than 5 parts per thousand. If you add too much MSG, people will feel dry mouth and sour after eating it.

Since MSG is alkaline, it should not be mixed with acidic dishes such as vinegar to avoid neutralizing the acid and alkali.

In addition, babies should eat less MSG, because MSG will form a complex with zinc in the human body, zinc glutamate, which will then dissolve in water and be excreted from the body, causing zinc deficiency in infants and affecting children's development.