1、營(yíng)養(yǎng)與健康（Nutrition and health）Nutrition and healthSection 1 nutrientsThe active ingredient in food is called nutrients. The human body needs nearly 50 kinds of nutrition, and can be divided into six broad categories, namely: protein, fat, carbohydrates, minerals (also known as inorganic salts, includin

2、g major elements and trace elements), vitamins and water.Protein 1Protein is the material base of life. Every tissue and organ of the human body, from hair, skin, muscle, blood, to the internal organs and brain, to the bone marrow, proteins are their main components. The protein in most tissues of t

3、he human body is constantly updated, that is, in constant decomposition and synthesis, an average of about 3% of the protein is updated daily. From infancy to adulthood, all tissues in the body need protein for constant growth and development. After the human body is injured, the tissue temporary re

4、pair also needs the protein.In addition, protein is the main raw material for the formation of human essential enzymes and hormones, or the raw material that constitutes antibodies. Protein can also provide heat energy, and each gram of protein is oxidized in the human body to provide about 5 thousa

5、nd and 650 calories of heat.Normal people need about 0.75 grams of high-quality protein per kilogram of body weight per day. Such as protein intake is too small, there will be dysplasia, anemia, weight loss, edema and other phenomena. If you eat too much, the body will transform these proteins into

6、energy and be released or converted to fat storage, and the transformation process of urea produced by the kidneys excreted, will increase the burden on the kidneys, unhealthy.Two, fatFat is the highest energy nutrient. A gram of fat produces 9 thousand and 450 calories of heat. Human subcutaneous,

7、visceral fat is the bodys thermal energy warehouse. In some special cases, such as hunger, when the bodys extremely limited glycogen is consumed, it can be transferred to the bodys thermal energy needs. Lecithin and phospholipids in fat form the main components of the brain and nerves. Fat is not ea

8、sy to conduct heat, excessive loss of subcutaneous fat layer can prevent body heat, can also prevent the heat environment into body too much, so that the heat preservation and heat insulation effect, to maintain normal body temperature. In addition, the fat surrounding the viscera can protect and se

9、cure some vital organs from mechanical friction and displacement, such as cushions, to avoid impact and vibration.The main source of fat is cooking oil, meat and other kinds of food. The body weighs 50 to 60 grams per kilogram of body weight per day.Three, sugarCarbohydrates are a large class of com

10、pounds composed of three elements, carbon, hydrogen and oxygen. Because it has the same proportion of hydrogen and water, it is also called carbohydrate. Sugar can be divided into monosaccharides, disaccharides and polysaccharides. Monosaccharide is the most simple sugars, can be directly absorbed a

11、nd utilized by the body, such as glucose, fructose and galactose; disaccharide is composed of 2 monosaccharides condensation, common disaccharide sucrose, lactose and maltose. Polysaccharides are mainly composed of glucose molecules, no sweet, mainly starch, dextrin, glycogen and dietary fiber. Amon

12、g them, dietary fiber can not be used for the human body, including cellulose, hemicellulose and pectin.The most important function of sugar is to supply energy. It is the most extensive, economical and most complete substance in the body. 4 thousand and 100 grams of calories can be produced per gra

13、m of sugar. Sugar is also a major component of nerve tissue, and all nerve cells and tissues contain carbohydrates.Foods with more carbohydrate content include Cereals, rhizomes and potatoes. Carbohydrates are scarce in the body and must be supplemented by meals several times a day. Adults weigh abo

14、ut 431.4 grams per kilogram per day.Four minerals1, calciumCalcium is the backbone of bones and teeth. When the body calcium deficiency, mainly affecting the development of bone and teeth, infants and young children will suffer rickets, adults showed osteomalacia, the elderly showed osteoporosis. Th

15、e sources of calcium are dairy products, kelp, seaweed, shrimp and soybeans.2, ironIron is an important component of blood. Iron deficiency can cause iron deficiency anemia when dietary iron is insufficient. People who suffer from iron deficiency anemia are infants, adolescents, women of childbearin

16、g age, etc. The main source of iron is the internal organs, blood, muscles of birds and livestock. The iron in these foods is easily absorbed by the body.The iron in vegetable food can be absorbed by the body after being converted into two valent iron through the action of gastric acid, and its qual

17、ity is inferior to animal food.3, zincAlthough zinc content is very little, it is very important to life. Zinc plays an important role in the synthesis of protein. When zinc deficiency occurs, it can cause growth retardation, sexual retardation, taste change, pica, and it is difficult to heal wounds

18、. The sources of zinc are mainly animal food, such as meat, seafood, poultry and so on.4, iodineIodine is an important component of thyroxine. Thyroxine is an important hormone, which plays an important role in promoting the growth of human body and regulating the speed of metabolism. If the thyroid

19、 gland is not secreted, it can cause growth arrest and affect the development of intelligence and personality. When dietary iodine deficiency, in order to get from the blood collection more iodine, thyroid cells will be increased, and the cell volume increases, so that the formation of goiter. The s

20、ources of iodine are mainly seafood, such as kelp, seaweed and so on.Five vitaminsVitamins are an organic compound necessary to maintain normal human life. It plays a very important role in the growth, development and metabolism of the organism. Vitamins can be divided into fat soluble vitamins (A,

21、D, E, K) and water-soluble vitamins (B, C, etc.).1, vitamin AVitamin A is closely related to vision. There are two different shapes of cells in the retina of the eyes. One is called the cone, and the other is called the rod cell. Lack of vitamin A will affect the normal work of rod cells, regulation

22、 of weak light, is suffering from night blindness. Vitamin A is also important for epithelial formation, development, and maintenance of epithelial tissue. It reduces infection of the respiratory tract in humans and prevents dryness and roughness of the skin. Vitamin A is also essential for normal b

23、one growth. It helps cell proliferation and growth. Vitamin A deficiency can occur growth arrest, but also affect fertility. Foods rich in vitamin A include animal foods, animal livers, nonfat milk and dairy products, and eggs. Vitamin A, or carotene, in vegetable foods.2, vitamin DVitamin D can reg

24、ulate calcium and phosphorus metabolism in the body and promote its absorption, thereby affecting bone calcification. Children lack of vitamin D susceptible to rickets, lack of adult D easy osteomalacia. Human vitamin D can be obtained in two ways. One is in the sunlight under UV irradiation, t dehy

25、drocholesterol by converting the skin; two is ingested through food, high fat content of fish, animal liver, egg yolk, high content of butter and cheese.3, vitamin B1The main function of vitamin B1 is to promote glucose metabolism. When vitamin B1 deficiency, the energy metabolism is not complete, r

26、esulting in pyruvate and other acidic substances, can damage the brain, nerves, heart and so on. Vitamin B1 plays an important role in growth and development, promoting appetite, normal peristalsis of the gastrointestinal tract and secretion of digestive juice. When the body lacks vitamin B1 to beri

27、beri, neuritis, lower extremity weakness etc. Vitamin B1 is high in cereals, legumes and meat.4, vitamin B2Vitamin B2 is involved in antibody metabolism and increases resistance. The lack of susceptibility to angular cheilitis, glossitis, oral mucosal ulceration, keratitis, dermatitis, etc. Meat, da

28、iry and eggs are higher.5, vitamin CVitamin C affects and participates in the formation of collagen. Collagen is a protein that can bind cells together like glue. When the wound is healed, vitamin C is needed to promote the formation of collagen and heal the wound. When the intake of vitamin C is in

29、sufficient, it can cause the body to reduce the resistance of the disease, the wound is not easy to heal, the capillaries are fragile, easy to rupture, causing subcutaneous bleeding, gingival swelling, bleeding, calcification, bad, irritability and burnout. When the body of a serious lack of vitamin

30、 C, can suffer from scurvy. Vitamin C can also promote the absorption of iron, lack of anemia. Fresh vegetables and fruits contain a lot of vitamin C.Six, the cheapest and most essential nutrients - waterWater is the source of life and an important part of all life. In human tissues, 90% of the bloo

31、d is water, and 72% of the muscle water.Hard bones also contain 25% of the water, and even 10% of the water is contained in the teeth. The physiological function of water has the following aspects:1. Water is a solvent for all nutrients and metabolic wastes. This is because water has a strong solven

32、t, and many substances are soluble in water.2, water directly participates in the oxidation-reduction reaction in vivo and promotes various physiological activities and biochemical reactions. Without water, all metabolic activities cannot proceed.3, water is the bodys own lubricant.4. Regulate body

33、temperature.Second, the nutritional value of various types of foodThere are many kinds of food available for human consumption, but none of the food contains all the nutrients the body needs. In order to meet the needs of the body for nutrients, people will always eat a variety of food mix, which re

34、quires first to understand the nutritional content of various types of food, quality characteristics.1. CerealCereals include rice, flour, corn, millet, sorghum and so on. They provide mainly heat, vitamins, B and minerals. The nutritional value of protein in cereals is lower than that of general an

35、imal foods, but it is still the major source of protein in Chinese people.Two, vegetables and fruitsVegetables and fruits mainly provide vitamins and minerals, which are the main sources of carotene, vitamin C, vitamin B2, calcium, and iron in the diet.Three. Animal foodAnimal food refers to the mea

36、t (such as pork, beef and mutton), poultry (chicken, duck and goose) organs (liver, kidney, heart, etc.) and aquatic products. In terms of nutritional value, animal food has high protein content and good quality. Animal foods also contain high levels of fat and contain fat soluble vitamins and miner

37、als. In addition, the nutritive value of animal offal is higher than that of common livestock and poultry. In addition to providing high quality protein, it contains many minerals and vitamins more than livestock and poultry meat.Four, eggs foodCommon eggs chicken, duck and goose, pigeon eggs etc. T

38、he composition and content of essential amino acids in egg proteins are more ideal than meat foods, and are high quality proteins. Most of the fat in the egg is found in the yolk and is easily absorbed by the body. Egg yolk is also rich in calcium, iron, vitamins B1 and B2.Five, milkMilk is one of t

39、he most nutritious foods. It contains nutrients essential to the human body. It is rich in protein and calcium that is easily absorbed and used. The characteristics of milk fat composition is rich in low melting point lower fatty acids and unsaturated fatty acids, and the dispersed particles are sma

40、ll, easily digested and absorbed; milk minerals including calcium, potassium, sodium, calcium and magnesium, which is particularly easy to be absorbed. Milk contains almost all of the known vitamins, of which vitamin A and vitamin B2 are prominent.Six, beans and bean productsMany kinds of beans, soy

41、beans (soybeans, green beans, black beans, beans, peas), mung bean, red bean. Legumes have high levels of protein and minerals, so legumes replace some cereals as staples, improving the quality and quantity of proteins in the diet.Third reasonable mealsAdolescence is the most productive period in on

42、es life. For young people, nutrition is not only to supplement the activities of life and learning, the consumption of life, but also to ensure human development and intellectual development of the important material base. Therefore, reasonable nutrition and balanced diet and good eating habits play

43、 an important role in their future life.First, what is a reasonable meal?Nutrients contained in the food range, the amount of adequate, appropriate proportion, the nutrients provided in the diet and the needs of the body to maintain balance, which is called a reasonable diet.Two, the requirements of reasonable meals1, diet structure should be balance

相關(guān)知識(shí)

營(yíng)養(yǎng)與健康（Nutrition and health）
China Health and Nutrition Survey — China Health and Nutrition Survey (CHNS)
Nutrition and Health Claims
Nutrition, Health, and Your Environment
Modern Nutrition in Health and Disease
Achieving Optimal Health: Wellness and Nutrition
Optimizing Nutrition and Hydration for Health and Wellness
Japanese Health and Nutrition information
Master of Health Sciences in Nutrition and Dietetics
Health Vocabulary (Fitness and Nutrition Vocabulary)

網(wǎng)址: 營(yíng)養(yǎng)與健康（Nutrition and health） http://www.u1s5d6.cn/newsview1703607.html