Three main energy substances and their energy supply order

The three major energy substances are sugar, fat and protein, and the order of energy supply is as follows:

1, sugar is the most important energy supply substance for human body, and it is also the first energy substance to be used. When the human body needs energy, it will first decompose the sugar in the body to produce energy. If glycogen is insufficient, it will decompose glucose in the body.

2. When sugar supply is insufficient, fat becomes the main energy-supplying substance of human body. Fat is stored in adipose tissue in the form of triglycerides, and energy is generated through the oxidation reaction of fatty acids. Compared with sugar, fat can provide energy supply for a longer time, but fat oxidation produces relatively less energy.

3. When sugar and fat are in short supply, protein can also be decomposed to generate energy. Protein is composed of amino acids, which are converted into energy through metabolism. However, protein is an important substance to maintain the structure and function of the human body, and should be avoided as much as possible as an energy substance.

The role of the three major energy sources:

1, providing energy: The three major energy substances are the necessary energy sources for the human body to maintain life activities. Carbohydrate and fat produce energy through oxidation reaction, which supplies the needs of various tissues and organs in the whole body. Protein can also be decomposed to generate energy, but it should be avoided as far as possible because of its importance.

2. Maintain body function: Carbohydrate is the main energy substance of human brain and red blood cells. Lack of carbohydrates can lead to brain dysfunction and anemia. Fat is an important component of cell membrane and myelin sheath, and also participates in regulating body temperature and protecting internal organs. Protein is the basic component of human muscles, bones, skin and other tissues and organs, and also participates in regulating physiological functions and maintaining blood osmotic pressure.

3. Save protein: When people eat enough carbohydrates and fats, they can reduce the decomposition and utilization of protein, thus saving protein. This is because protein produces less energy by oxidation compared with carbohydrates and fats, and protein is an important substance to maintain the structure and function of human body. Excessive decomposition can lead to physical damage.