The human body needs a lot of nutrients, so China put forward the saying that "five grains are the supplement, five fruits are the help, five animals are the benefit, and five vegetables are the supplement" in ancient times, which fully embodies the diversity of diet. In daily life, the best way to achieve nutritional balance is to eat a variety of foods, learn from each other's strengths, and achieve a scientific and reasonable diet. At the same time, the supplement of nutrients must be comprehensive and balanced, especially vitamins and minerals, because there is a strong synergy between them.

Generally speaking, the nutrients needed by human body include protein, fat, carbohydrate (sugar), water, minerals and vitamins.

1. protein

Protein is a substance closely related to life and various forms of life activities, and protein participates in every cell and all important components of the body. There are many kinds of protein in human body, with different properties and functions, but they are all composed of more than 20 kinds of amino acids in different proportions, which are constantly metabolized and updated in the body. The ingested protein is digested and decomposed into amino acids in the body, and then it is recombined into human protein in a certain proportion in the body after being absorbed. At the same time, the new protein is constantly metabolized and decomposed, keeping them in dynamic balance. Therefore, the quality and quantity of food protein and the proportion of various amino acids are all related to the amount of protein synthesized by the human body, especially the growth and development of teenagers, the prenatal and postnatal care of pregnant women and the health and longevity of the elderly, which are closely related to the amount of protein in the diet.

2. Fat

Fat is an important part of body tissue and the main raw material for supplying heat. Both protoplasm and cell membrane in cells contain fatty compounds. More than 95% of the lipids in food are triglycerides, in addition to cholesterol lipids and phospholipids.

3. carbohydrates

Carbohydrates, also known as carbohydrates, are an important class of organic compounds that exist most and are widely distributed in nature. Glucose, sucrose, starch and cellulose are all carbohydrates. Carbohydrate is the main source of energy needed by all living things to maintain life activities. It is not only a nutrient, but also has special physiological activity. For example, heparin in the liver has anticoagulant effect; Blood sugar is related to immune activity. In addition, the components of nucleic acid also contain carbohydrates-ribose and deoxyribose.

4. Water

Water is an inorganic substance composed of hydrogen and oxygen, and it is a colorless and odorless transparent liquid at normal temperature and pressure. In nature, pure water is very rare, because water is usually a solution of acid, alkali, salt and other substances.

5. minerals

Minerals are the general term for inorganic substances in human body. Like vitamins, they are all essential elements for human body, and minerals cannot be produced and synthesized by themselves. The daily mineral intake of human body is basically certain, but it varies with age, gender, physical condition, environment, working conditions and other factors. There are about 50 minerals in the human body. Although they only account for 4% of human body weight, they are essential components of organisms.

6. Vitamins

Vitamins, also known as vitamins, are a kind of organic substances necessary to maintain human life activities and important active substances to maintain human health. The content of vitamins in the body is very small, but it plays an important role in the process of human growth, metabolism and development.