Encyclopedia of Family Medicine

Chapter 6 Human Body and Nutrition (6)
(11) Vitamin B12.Anti-fatty liver, promote the storage of vitamin A in the liver, promote cell maturation and body metabolism; treat pernicious anemia.

(12) VITAMIN C.Connect bones, teeth, and connective tissue structures; it has the function of bonding between cells in the capillary wall, increases antibodies, enhances resistance, and promotes red blood cell maturation.

Vitamin B15 and Vitamin B17
Vitamin B15 and vitamin B17 are food ingredients that are beneficial to human health proposed by some foreign nutrition scholars, and named as vitamins, but they have not been recognized by world scholars so far.

The so-called vitamin B15, according to advocates, is "pandextrin" extracted from grains.Actually it is "Dimethyl Acetate Hydrochloride".What is used clinically is artificially synthesized vitamin B15, which is not the same thing as the "natural vitamin B15" of Su Yiyang.It is mainly used to fight fatty liver and improve the oxygen metabolism rate of tissues.It is sometimes used to treat coronary heart disease and chronic alcoholism.

Vitamin B17 is a kind of amygdalin contained in the seeds, roots, stems, and leaves of some Rosaceae plants belonging to the same genus as apricots—loquat, plum, plum, peach, apple, etc.It hydrolyzes in the human body to produce hydrogen cyanide and benzaldehyde, which is highly toxic.The so-called vitamin B17 can strengthen the body and cure diseases, and has miraculous effects in curing cancer, but it is just a deceptive means for businessmen to sell products.

In terms of nutrition, the so-called vitamins should be a class of substances that cannot be synthesized by the human body (or the amount of synthesis cannot meet the needs) but are indispensable in the normal metabolic process and regulation of physiological functions of the human body.They must be nutrients supplied by food.Therefore, certain typical clinical symptoms will appear when there is a deficiency.So far no deficiency has been found due to the lack of amygdalin, so these two substances cannot be called vitamins at all.

The important role of minerals
Minerals (also known as inorganic salts) are compounds or natural elements that occur naturally in the earth's crust.There are more than 50 kinds of minerals in the human body. Although they only account for 4% of the body weight in the human body, they are an essential part of the organism.According to their content in the body, they can be roughly divided into two categories: macro elements and trace elements.A large number of common elements are carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur and calcium, magnesium, potassium, sodium, chlorine.The first six are the main components of protein, fat, carbohydrate and nucleic acid.It is also the most basic element of living organisms.The other types are also the necessary components to form bones, teeth, muscles, nerves, blood, glands, various body fluids, secretions, hair, nails, etc. They are not only the building materials of the body, but also can regulate physiological functions.In addition to carbon, hydrogen, oxygen, and nitrogen, the others are called mineral constant elements.

The content of trace elements in the human body is very small, and the total amount is less than five ten thousandths of the body weight.Such as iron, zinc, copper, manganese, chromium, selenium, vanadium, iodine, etc.With the development of science, people's understanding continues to expand, and the number of these trace elements will increase.The most prominent function of trace elements is that they are closely related to the vitality of life, and only an amount as small as a match head or less can exert a huge physiological effect.It is worth noting that these trace elements must be directly or indirectly supplied by the soil.Trace elements also play a role that cannot be ignored in terms of disease resistance, cancer prevention, and longevity.

essential trace elements

According to scientific research, so far, 16 kinds of essential trace elements have been confirmed to be related to human health and life, namely iron, copper, zinc, cobalt, manganese, chromium, selenium, iodine, nickel, fluorine, molybdenum, vanadium , tin, silicon, strontium, boron.Each trace element has its special physiological function.Although they are present in very small amounts in the human body, they are necessary to maintain some crucial metabolisms in the human body.Once the lack of these essential trace elements, the human body will appear disease, even life-threatening.It has been reported abroad that the reduction of the total amount of iron, copper, and zinc in the body can weaken the immune mechanism (the ability to resist disease), reduce the ability to resist disease, encourage bacterial infection, and the mortality rate after infection is also high.

The main functions of trace elements in the human body are:

(1) Carry constant elements and bring a large number of elements to various organizations.

(2) Act as the active center of various enzymes in the organism to promote metabolism.

(3) Participate in the action of various hormones in the body, such as zinc can promote the function of sex hormones, chromium can promote the action of insulin, etc.

Trace elements and health

Trace elements are closely related to human health.In recent years, trace elements are considered to be a promising new field related to human health and longevity, and have attracted widespread attention from the nutrition and medical circles at home and abroad.So, what is the relationship between trace elements and health?Let's take a look at how some trace elements affect human health.

cobalt element.Is an important component of vitamin B12.Cobalt plays an important role in the synthesis of protein, fat, carbohydrate metabolism and hemoglobin, and can dilate blood vessels and lower blood pressure.However, excessive cobalt can cause polycythemia, gastrointestinal dysfunction, deafness, and myocardial ischemia.

Fluorine element.Fluoride is a normal component of human bones and teeth.It can prevent dental caries and prevent osteoporosis in the elderly.However, eating too much fluorine will cause fluorosis and "plaque disease".When there is too much fluoride in the body, skeletal fluorosis can also occur, causing spontaneous fractures.

Chromium element.It can help insulin play a role, prevent arteriosclerosis, promote protein metabolism and synthesis, and promote growth and development.However, when the content of chromium increases, such as long-term inhalation of chromate powder, lung cancer can be induced.

From this point of view, although trace elements are particularly important to the human body, too much or too little intake can cause diseases.At present, many endemic diseases and some tumors are found to be related to trace elements.

The important role of salt

The main component of table salt is sodium chloride, and it also contains a small amount of potassium, magnesium, calcium and other elements necessary for human physiology.Salt is essential to human health.Since ancient times, people have valued salt.Li Shizhen said in "Compendium of Materia Medica": "Among the five flavors, only this is indispensable." Why is salt so important?This is because the human body does not get enough salt and becomes sick.If the heart does not have it, it will affect the normal beating. If it is missing in the stomach, it will cause gastric acid deficiency and indigestion and loss of appetite.If you don't eat salt for a long time, people will be weak, dizzy, muscle twitching, etc., which is called "salt loss disease" in medicine.Salt plays an important role in maintaining the osmotic pressure and acid-base balance of body fluids, maintaining the irritability of nerves and muscles, and regulating physiological functions.In addition, salt also has bacteriostatic, sterilizing, and antiseptic effects.Since the role of salt is so important, some people think that if you want to be strong, you need more salt. This view is also one-sided and wrong.
It is generally believed that adults need about 2-3 grams of salt per day, up to 7 grams.Do not increase the amount of salt except for excessive sweating or urination due to high temperature, strong labor, chronic diarrhea or taking diuretics.Too much salt will increase the burden on heart and kidney function and become a factor that is harmful to health.It has been scientifically confirmed that excessive salt is also closely related to high blood pressure.In addition, too much salt is not good for patients with respiratory diseases, exacerbating asthma and chronic bronchitis and increasing sputum volume.For ulcer disease, acute rheumatism, obesity, coronary heart disease, liver cirrhosis and ascites, restricting the amount of salt is also an extremely important treatment measure.

The nutritional function of the six elements

iron.Iron content in the human body is about 4 to 5 grams.The function of iron in the human body is mainly to participate in the formation of hemoglobin and promote hematopoiesis.The content in hemoglobin is about 72%.Iron content is higher in spinach, lean meat, egg yolk, and animal liver.

copper.The normal adult body contains 100-200 mg of copper.Its main function is to participate in the hematopoietic process, enhance disease resistance, and participate in the formation of pigments.Copper is high in animal liver, kidney, fish, shrimp, and clams, as well as in fruit juice and brown sugar.

zinc.It plays an important role in various physiological functions of the human body.Participates in the synthesis of various enzymes; accelerates growth and development, enhances the regeneration ability of wounded tissue, enhances resistance, and promotes sexual function.Zinc is found in high concentrations in fish, meat, animal liver and kidney.

fluorine.It is a normal component of bones and teeth.It can prevent dental caries and prevent osteoporosis in the elderly.Foods with more fluorine include grains (wheat, rye flour), fruits, tea, meat, vegetables, tomatoes, potatoes, carp, beef, etc.

selenium.Adults need about 0 mg per day.Selenium has antioxidant properties, protects red blood cells, and has been found to prevent cancer.Selenium is abundant in wheat, corn, Chinese cabbage, pumpkin, garlic and seafood.

iodine.Thyroxine exerts physiological functions, such as promoting protein synthesis and activating more than 100 enzymes; regulating energy conversion; accelerating growth and development; maintaining the structure of the central nervous system.Iodine is rich in kelp, seaweed, sea fish, sea salt, etc.

elements that affect the human body

calcium.Although most of the calcium in the body exists in the bones and teeth, and it is rarely dissolved in the blood, it plays a very important role.For example, it cooperates with magnesium, potassium, and sodium to regulate neuromuscular excitability and maintain the normal function of the myocardium. Calcium also participates in the blood coagulation process.

Potassium.It plays an important role in maintaining fluid osmotic pressure and acid-base balance in the human body.When the intake is reduced, symptoms such as whole body fatigue, drop in blood pressure, polyuria, intestinal infarction, etc. will occur. In severe cases, death may occur due to difficulty in breathing and heart disease.

magnesium.It is the main component of bones, teeth and cytoplasm. It can also regulate the activities of nerves and muscles, maintain the acid-base balance in the body, and activate various enzymes in the body.Symptoms such as tremors, athetosis and even convulsions can occur in humans due to magnesium deficiency.

sodium.It can maintain water balance, acid-base balance and neuromuscular irritability in the body.Symptoms of sodium deficiency: fatigue, dizziness, nausea, loss of appetite, rapid heartbeat, weak pulse, drop in blood pressure, muscle spasm, etc. In severe cases, coma may occur.

chlorine.Chlorine accounts for about 0% of the body weight and is distributed in various tissues of the body, with the most in cerebrospinal fluid and gastrointestinal secretions.Chlorine is a component of hydrochloric acid, which can maintain the normal acidity of human gastric juice and help maintain the acid-base balance of body fluids.

phosphorus.It is an important component of bones, teeth and nerve tissue. More than 80% of phosphorus in the human body exists in bones and teeth.It participates in the metabolism of carbohydrates, fats and nucleic acids in cells, and plays an important role in maintaining the normal function of nerves and muscles and the acid-base balance in the body.

reasonable cooking method

The quality and quantity of nutrients contained in various foods will change to a certain extent during the cooking process, and the degree of change is closely related to the physical and chemical characteristics of the food itself and cooking methods.How to not only let people eat delicious meals, but also keep the nutrients in the food to the greatest extent, the general method is;

Rice noodles.The longer the rice is soaked in water, the higher the temperature of the rice washing water, the more times the rice is washed, the whiter the rice, and the more the loss of nutrients.to correct these practices.After the rice is cleaned, the soaked rice water and rice can be cooked in the same pot to reduce nutrient loss.When cooking noodles and dumplings, most of the water-soluble vitamins are dissolved in the soup, and the soup cannot be thrown away.Too much alkali when making steamed buns or pancakes can destroy thiamine and riboflavin.Due to the addition of alkali and hot frying, the thiamine will be completely destroyed.The roasting, steaming, and roasting methods have less damage to vitamins and are easy to digest.

Vegetables.Vegetables must be washed first and then cut. Do not boil the vegetables in boiling water before frying them. Use high heat and stir-fry them quickly. For example, adding a little vinegar, starch or broth when cooking can stabilize the vitamin C in the vegetables. effect.Generally, iron pans are used for cooking, and copper pans will cause vitamin C to be oxidized and lost.

animal class.In animal foods such as meat, fish and eggs, except vitamins are damaged during cooking, other nutrients are only denatured, and the total content does not change much.When meat is cooked, part of the nutrients are dissolved in the soup, and the loss of nutrients in the same soup is less.Vitamins in meat are lost in different amounts with different heating methods.60-65% of vitamin B1 is lost when braised or stewed pork, 45% is lost when steamed and fried, and 13% is lost when fried.When cooking meat, add less water and simmer until it is cooked.

The seventh nutrient that cannot be ignored
Dietary fiber refers to the plant-based substances that are not digested in the human intestine.It includes cellulose, hemicellulose, pectin, algin, lignin and other polysaccharide substances that were thought not to be utilized by the body in the past.Modern scientific research has confirmed that dietary fiber is not just the residue of food as people traditionally know, but an indispensable nutrient for human beings to cure diseases and prolong life. It is called the seventh nutrient (the other six nutrients are carbohydrates, fats, proteins, etc. , minerals, vitamins and water).

Although humans cannot digest dietary fiber like herbivores, they can decompose part of the fiber with intestinal bacteria.For example, Escherichia coli can synthesize fiber into vitamin B-type pantothenic acid, inositol and vitamin K to be absorbed by the human body.

Dietary fiber has the functions of expanding the volume of feces, good water absorption, promoting intestinal peristalsis, accelerating the propulsion of feces in the intestinal tract, making defecation timely, reducing the contact time between the intestinal cavity wall and ingested carcinogens, and eliminating the risk of colorectal cancer.The cellulose intake of Europeans and Americans is only 1/6 of that of Africans. 10 out of 42 people in the United States suffer from colorectal cancer, while only 8 people in Africa suffer from colorectal cancer.Dietary fiber can also reduce the incidence of gastric cancer and lung cancer, and has preventive and therapeutic effects on constipation, hemorrhoids, and diabetes.In addition, dietary fiber has a good effect on preventing coronary heart disease and cholelithiasis.

Too much dietary fiber may affect the absorption of calcium, iron and some vitamins.But if the right amount is mastered, the advantages will outweigh the disadvantages.As long as we have a reasonable mix of coarse and fine grains, and eat more vegetables and fruits, dietary fiber will do wonders for your health and longevity.

Calculation of calories in food
The so-called heat of food refers to the potential energy in the food, and the unit of energy is usually expressed in the unit of heat energy.In physics, the heat required for 1 gram of water to rise by 15 degree from 1°C is called 1 calorie, or a small calorie.Nutrition uses kilocalories, usually called kilocalories.The heat required to raise the temperature of 1 kg of water from 15°C to 16°C is 1 kcal.We say that a certain food contains 1 kilocalorie, that is, the heat released by burning the food can make 1 kilogram of water rise 15 degree from 1 ℃.Another example is that an apple contains 87 kcal of heat, that is to say, after digestion, absorption, oxidation and decomposition, the heat generated by this apple can raise the temperature of 87 kg of water by 15 degree from 1°C.

Energy supply is the basis of human life activities. No matter the physiological processes such as heartbeat, respiration, maintenance of body temperature, nerve excitation, glandular secretion, etc., energy is required. These energy mainly come from the three major nutrients in food, namely carbohydrates and lipids. and oxidative breakdown of proteins in the body.Each gram of sugar and protein oxidized in the body can produce 4 kcal of heat, and fat can produce 9 kcal of heat energy.Therefore, the three major nutrients are called the energy substances of the human body, or fuel.

Our body is an organism composed of billions of cells. Each cell is a chemical factory that uses nutrients and oxygen to generate energy, and is also a conversion station for different forms of energy. For example, muscle cells can convert heat energy into Mechanical energy, which enables a person to generate force to do work.If a person eats a 12mm long sugar cube, he will gain the energy to climb dozens of skyscrapers.

(End of this chapter)