1, the variety of food is complete, the quantity is sufficient, and the proportion is appropriate.

Su Wen in Huangdi Neijing, a classic work of Chinese medicine from the Warring States to the Western Han Dynasty more than 2,000 years ago, put forward the principle of "five grains for nourishment, five fruits for help, five animals for filling, five vegetables for filling, and the concept of infiltration is reasonable diet".

The types of food we eat three times a day include grains, meat and eggs, milk beans, fruits and vegetables. The types and contents of nutritional components and dietary beneficial components in different foods are different. No food (except the breast milk of a 6-month-old baby) can meet the energy and all the nutrients needed by the human body.

Food diversification is the basic principle of balanced dietary pattern. In order to meet the daily demand for energy and nutrients, it is necessary to ensure the diversification of food. The daily diet should include five kinds of food, with an average intake of more than 12 kinds per day and more than 25 kinds per week. The intake of various foods should be appropriate to ensure the appropriate proportion of food intake of animals and plants.

2. Food should be safe and hygienic.

The choice of ingredients should be clean, safe and hygienic. Do not eat contaminated or over-standard or deteriorated foods such as microorganisms and their toxins, additives, chemicals and pesticide residues. On the one hand, this kind of food can not meet the nutritional needs of the human body; On the other hand, it will also cause acute and chronic harm to human body, and even lead to the occurrence and development of malignant tumors.

3. Scientific and reasonable cooking and processing

In the process of food processing, we should minimize the loss of nutrients, improve the digestion and absorption rate of food, improve the sensory characteristics of food, stimulate appetite, and eliminate anti-nutritional factors, harmful chemicals and harmful microorganisms in food. Reasonable cooking and processing is conducive to the preservation of nutrients.

For example, the preservation rate of B vitamins in rice steaming is higher than that in soup steaming. In the process of meat processing, the external protein of meat can be solidified rapidly by sizing and rapid frying, which can reduce the spillover loss of nutrients; Wash vegetables before cutting, fry them quickly and eat them now, which can effectively reduce the loss of vitamins during cooking.

4. Develop good eating habits and ensure a reasonable dining system.

A reasonable dining system is helpful to increase appetite, promote the rhythmic secretion of digestive juice, and make food fully absorbed and utilized in the body. Adults should eat three meals a day on time and develop good eating habits such as not being picky about food, not being partial to food and not overeating. Arrange meals reasonably according to labor intensity and physical condition.

Development of China Residents' Dietary Pagoda

Many countries have formulated dietary guidelines to guide residents to eat reasonably. In China, Dietary Guide for China Residents and Balanced Dietary Pagoda for China Residents were published in 1997.

With the development of social economy in China, the dietary consumption and nutritional status of China residents have changed greatly. In order to guide residents to better balance their diet, obtain reasonable nutrition and improve the national health level, China Nutrition Society issued a new edition of Dietary Guidelines for China Residents (2007) (hereinafter referred to as Dietary Guidelines) and Dietary Pagoda for China Residents (2007) (hereinafter referred to as Dietary Pagoda).

Compared with the Diet Pagoda (1997), the tower foundation of the Diet Pagoda (2007) added potatoes and miscellaneous beans on the basis of the original grain, and the beans and bean products on the fourth floor of the tower were changed to soybeans and nuts, and the content of salt at the top of the tower was increased by 6g.

The recommended intake of vegetables, fruits, fish, shrimp, milk, dairy products and oil has increased, while the recommended intake of grains, livestock and poultry meat has decreased. In Dietary Pagoda (2007), the drinking mode, the content of 1200ml water, the physical activity mode and the suggestion of "6000 steps of physical activity" were also added.