"Shi Lichuan" said: "Food is the most important thing for the people", which shows that diet is an indispensable condition to ensure survival. Everyone needs to eat as long as he is alive. Eating is the expression of life activities and the guarantee of health and longevity. "Guxing, Guwei." "People's safety must be based on food."

Therefore, diet not only maintains individual life, but also relates to the continuation of race, the prosperity of the country, the prosperity of society and human civilization. People's diet is digested and absorbed by the spleen and stomach, and transformed into human qi and blood semen through the viscera, which is distributed throughout the body and nourishes the viscera and limbs.

The traditional way of keeping in good health in China pays special attention to diet. Li Shizhen, a medical scientist in the Ming Dynasty, once said that "dieters are the lifeblood of human beings". In order to keep healthy, we must start with diet and really understand the science and methods of diet.