Spring diet should be light, eat more vegetables and some edible fungi, such as black fungus, tremella, mushrooms, mushrooms and so on. There are many viruses in spring, and many viruses will enter your body. Eating more edible fungi can increase your antiviral ability. In summer, light, bitter, cold, nutritious and digestible food is better, emphasizing the spleen and stomach to promote digestion and absorption. In summer, when the temperature is high, people sweat more and drink more water, the gastric acid is easily diluted, the secretion of digestive juice is relatively reduced, and the digestive function is weakened, resulting in loss of appetite. In addition, in hot weather, people are greedy for raw and cold food, which leads to gastrointestinal dysfunction, or unclean food can easily lead to gastrointestinal discomfort and even food poisoning. Therefore, the diet in summer should be light, which can promote appetite, so as to achieve the purpose of health care. Eat more fruits and bitter foods, such as plows, watermelons and bitter melons. Summer is very hot, hot and humid. Eating watermelon and bitter food can clear away heat and relieve summer heat, dry dampness and strengthen spleen, and increase appetite. Sour food can be astringent, and sweating in summer is easy to hurt yin. Eating acid can stop sweating and diarrhea. For example, tomatoes have the functions of promoting fluid production, quenching thirst, invigorating stomach and promoting digestion, cooling blood and calming liver, clearing away heat and toxic materials, and lowering blood pressure. The weather is getting colder in autumn, and people's mouth, nose, skin and other parts often appear different degrees of dryness. So they should eat some nourishing, moist and juicy food, and eat less spicy and fried food. At the same time, Chinese medicine believes that the relationship between lung and autumn qi is very close, so we should eat more foods that moisten lung and promote fluid production. Suitable foods for autumn are: lily: it has the functions of nourishing and moistening the lungs, clearing away heart fire and calming the nerves, eliminating fatigue, moistening dryness and relieving cough. Lotus seed: it can not only remove residual heat, but also nourish and strengthen the body. It is a timely tonic in autumn. Yam: it is characterized by tonic without stagnation, neither hot nor dry, and is suitable for men, women and children. In winter, the climate is cold, with yin flourishing and yang declining. Under the influence of cold temperature, the physiological function and appetite of human body will change. Therefore, it is very necessary to adjust the diet reasonably, ensure the sufficiency of essential nutrients, improve the cold tolerance and immune function of the elderly, and make them spend the winter safely and smoothly. First of all, we must ensure the supply of heat energy. Such as lean meat, eggs, fish, milk, beans and their products. Protein contained in these foods is not only easy for human body to digest and absorb, but also rich in essential amino acids with high nutritional value, which can increase human body's cold resistance and disease resistance. Winter is also the off-season of vegetables. Vegetables are few in quantity and monotonous in variety, especially in northern China. Therefore, often after a winter, the human body appears vitamin deficiency, such as vitamin C deficiency, which causes many elderly people to have symptoms such as oral ulcer, root swelling and pain, bleeding and constipation. Its prevention and control method should first expand the food source, and the green leafy vegetables are relatively reduced in winter, so you can eat some potatoes, such as sweet potatoes and potatoes. Are rich in vitamin C and vitamin B, especially lack of vitamin A, and red sweet potatoes also contain more carotene. Eating more potatoes can not only supplement vitamins, but also clear away heat and eliminate plague. In addition to Chinese cabbage, cabbage, radish heart, white radish, carrot, bean sprouts, mung bean sprouts, rape and so on. It should also be selected in the main course listed in winter. These vegetables are rich in vitamins. As long as the varieties are changed frequently and matched reasonably, the vitamin demand of the human body can still be supplemented. The cold in winter will also affect the nutritional metabolism of the human body and increase the consumption of various nutrients to varying degrees. Due to the influence of digestion, absorption and metabolism in the body, the elderly often lack potassium, calcium, sodium, iron and other elements. In addition, the inorganic salts discharged with urine in winter increase, which should be supplemented in time. You can eat more foods rich in calcium, iron, sodium and potassium, such as shrimp, shrimp skin, sesame paste, pork liver and bananas. If there is low sodium, it tastes slightly salty when cooking, so it can be supplemented.