Vitamin A is a necessary substance to maintain the normal function of all epithelial tissues in human body, and it plays an adhesive and protective role on cells. If vitamin A is lacking, the body will have dry skin, keratinization and hyperplasia. Therefore, corneal or conjunctival dryness is closely related to the lack of vitamin A in the body. When vitamin A is deficient in the body, rhodopsin synthesized in retinal rod cells decreases, which reduces people's sensitivity to weak light and their ability to adapt to sunlight, and can lead to night blindness in severe cases. Foods rich in vitamin A are: pig liver, sheep liver, beef liver, eggs, milk, milk powder, cream, cheese and other dairy products, saury, flounder, salmon liver and so on. Foods containing carotene or carotenoids, such as carrots, tomatoes, red peppers, spinach, lettuce, etc. 2. Riboflavin (vitamin B2): When the human body lacks riboflavin, the eyes will be afraid of light, tears, itching or burning, leading to visual fatigue. Foods rich in riboflavin include pig heart, sheep heart, cow heart, animal kidney, lean meat, eggs, milk, green leafy vegetables, yeast and so on. Myopia patients should not only eat foods rich in vitamin A and riboflavin, but also eat more fruits such as oranges, sweet oranges and lemons. They should also eat more fish and eat less sweets such as candy, snacks and cheese. People with hyperopia usually need to eat more dried fruits, onions and skim milk. Cataract patients should not only drink more water and eat more vegetables, but also pay attention to eating more calcium-containing foods, such as milk and cheese, and should quit smoking and drinking.