2. protein is the basic component of human tissues and an important material foundation of the body. Every cell and all important components of the body need protein's participation, and protein is digested and decomposed into amino acids in the human body. It can be said that there would be no life without protein.
3. Fat: It is another nutrient that the human body needs. Include neutral fats and lipids. The important physiological functions of fat include providing essential fatty acids; Carrying fat-soluble vitamins; Provide heat energy to make meals feel full.
4. Carbohydrate: It is the most economical and main source for human beings to get calories from diet. Including monosaccharide, double grain, polysaccharide and dietary fiber in food.
5, minerals: also known as inorganic salts. It has been found that there are more than 20 kinds of inorganic salts necessary for human body, among which the relatively stable ones are called macronutrients, such as calcium, phosphorus, potassium, magnesium, sulfur and chlorine. The rest of the content is small and fluctuates greatly, which is called no trace elements, such as copper, iron, iodine, zinc, manganese and selenium.
6. Vitamins: They can be divided into two categories, namely fat-soluble vitamins such as vitamins A, D, E and K and water-soluble vitamins such as vitamins B and C. They do not provide constituent tissues, but participate in many cell activities. Although the human body needs very little, the lack of any vitamin will seriously affect the physiological metabolism, which is very important for maintaining human health.
7. Cellulose is a carbohydrate. Include cellulose, hemicellulose, lignin, pectin, etc. After ingestion, it will not be digested and absorbed by the human body, and waste residue will be formed in feces and excreted, but it can promote intestinal peristalsis, and at the same time attach excess fat and cholesterol to excrete, effectively preventing the occurrence of cardiovascular diseases and gastrointestinal diseases in adults, such as colorectal cancer.