In life, doctors often recommend "light diet", whether it is after surgery, after a serious illness, or for the treatment of chronic diseases such as hypertension and hyperlipidemia. So, what is the light diet that we often talk about? The original meaning of light diet. According to Cihai and Modern Chinese Dictionary, "Qing" originally refers to the transparency of water, often referring to the lack of color and smell, and the lack of fat in food. "Light" usually means that the taste is not strong, the color is light, or the taste is not salty. It can be seen that the original meaning of light diet is a diet with less oil and salt. With the sustainable development of social economy and the continuous improvement of people's living standards, the proportion of residents eating out is increasing. The use of oil and salt in canteens, restaurants and processed food deserves our attention. Don't use seasonings indiscriminately when cooking delicious food. In daily life, it is inevitable to use various seasonings when cooking dishes. Although condiments are necessary for cooking dishes, they can change the color and taste of dishes. However, improper use of condiments can also cause diseases. One of the items that is easily ignored is salt. Excessive salt intake is closely related to the increasing prevalence of hypertension year by year. It has been reported that the prevalence of hypertension in adults in China increased from 14.77% in 1991 to 32.67% in 2015, an increase of 17.9 percentage points in 25 years, and the prevalence of hypertension in men is higher than that in women. If too much fat is consumed in the diet, it will also cause hyperlipidemia and obesity. According to the Report on Nutrition and Chronic Diseases of Chinese Residents (2020), there are 200 million people with dyslipidemia in China, including 19% and 10.4% overweight/obesity rates for children and adolescents aged 6-17 and under 6, respectively, and 34.3% and 16.4% overweight and obesity rates for adult residents, which means that more than half of the adult residents are overweight or obese. In recent years, with the improvement of living standards, people pay more and more attention to the nutrition and hygiene of diet, but more and more seasonings are used in diet, which must be paid attention to. Generally speaking, the meaning of light diet is expanded on the basis of less oil and salt, and also includes requirements for sugar, spicy seasoning, etc. At this stage, the basic meaning of light diet refers to a diet with low salt, low fat, low refined sugar, and low spicy stimulation. For ordinary adults, "low salt" means that the daily intake of salt does not exceed 5 grams; "Low fat" means that the daily cooking oil consumption shall not exceed 25-30g, and the daily dietary heat ratio of fat shall be 20% - 25%, with a maximum of 30%; "Low refined sugar" means that the intake of refined sugar (such as sucrose) in the daily diet is less than 10% of the total energy, and the daily intake of sugar is not more than 50 grams, preferably less than 25 grams; "Smoked and spicy" refers to eating less spicy food such as pepper and chili, less smoked food such as bacon and smoked sausage, and less smelly food such as preserved eggs and stinky tofu. A light diet is not equal to a basic vegetarian diet. When it comes to a light diet, many people will say that vegetarian dishes with less oil and salt are not all light. In fact, this idea of equating light diet with basic vegetarian diet,