You can eat strawberries, oranges, sweet peppers and broccoli in winter to prevent colds. Vitamin C has the functions of antioxidation and immunity enhancement, and can relieve cold symptoms and shorten the course of disease. Strawberries and oranges can quench thirst, relieve sore throat and cough, and are also rich in vitamin C. You only need to eat five or six strawberries or an orange every day to meet the vitamin C needed by the human body. They are cheap cold-proof weapons. The content of vitamin C in sweet pepper is higher than other citrus fruits, which is suitable for raw food. Broccoli and other cruciferous vegetables contain a compound that can prevent and treat respiratory inflammation and reduce the incidence of respiratory infections and colds.