Productive nutrients: that is, "heat source", refers to all the nutrients that people consume every day, which can produce energy in the body, and is called "productive nutrients" in nutrition. Productivity nutrients are mainly composed of protein, lipids and carbohydrates.

Among them, protein protein accounts for about 16% of human body weight, and is used to make various body organs such as muscles, blood and skin. Each gram of protein provides 4 kilocalories, and the daily intake of protein should be equivalent to 10%- 15% of the total daily calorie intake. Protein is composed of various amino acids, but there are 20 different amino acids in human tissues. Different combinations of these amino acids can be made into various protein, which have different functions in human body.

Its main functions include the following aspects:

1. Repair body tissue

2. Make new body tissues, including skin, hair, nails, bones, muscles, organs, etc. , promote physical growth.

3. Produce enzymes and hormones to promote various functions of the body.

4. Make antibodies to enhance immunity and resist bacteria and infections.

5. It has anti-fatigue effect.

6. Adjust the water balance in the human body and maintain body fluids.

7. Help deliver oxygen and nutrients.

8. Provide energy.