Color blindness and color weakness are both conditions of impaired ability to distinguish colors; such patients are unable to distinguish various colors or certain colors in the natural spectrum, or have a weak ability to distinguish colors. The two are usually not strictly distinguished from each other, but differ in severity, and color blindness tablets help such patients to distinguish colors. Color blindness and color weakness are hereditary, with red-green color blindness being more common and predominant in males. People with blue-yellow color weakness need to pay more attention to the protection of their eyesight, which can be improved from the aspect of diet, and they can consume foods containing the following elements. First, foods containing vitamin C. Vitamin C is one of the components of the lens of the eye, vitamin C deficiency may cause clouding of the crystal, one of the causes of cataracts, usually eat more green peppers, cauliflower, raw pears and other foods. Second, foods containing vitamin A. Vitamin A can prevent the conjunctiva and cornea dryness, prevention and treatment of “dry eye disease”. For people who live in dry climates and wear contact lenses all year round, it is recommended to consume more foods containing vitamin A. Vitamin A also enhances the eye’s ability to respond to darkness. Vitamin A can also enhance the ability of the eyes to adapt to the dark environment, such as pig liver, milk, carrots and so on. Thirdly, foods containing calcium. If the diet lacks calcium will cause neuromuscular excitability increases, so the eye muscles will be in a high state of tension, it is easy to cause damage to vision over time. Calcium-containing foods mainly include lean meat, dairy, eggs, beans, vegetables and so on. Fourth, alkaline food. Eye fatigue is usually caused by the acid bismuth metabolites in the eye so that the eye environment is acidic, long time do not pay attention to the rest of the eye is easy to form myopia and amblyopia, therefore, Shu Jie reminds, to consume more coarse rice, apples, citrus, kelp and other alkaline foods.