The causes of senile cataracts are not well understood to date. It is especially important for the elderly to take care of their eyes in normal times. Preventive measures may include the following: 1. Increase nutrition: eat more fruits and vegetables and other foods with high vitamin content, prevent ultraviolet radiation, wear sunglasses with ultraviolet protection when the sun is strong, and often use eye medications or oral medications that are beneficial to lens metabolism. Patients suffering from diabetes or other endocrine – metabolic diseases should be treated in a timely manner, early control of blood sugar. 2, usually pay attention to the maintenance of eyes: reading and writing, watching TV time should be properly controlled. Go outdoors every 1-2 hours to let your eyes rest for a while, and do not read in the dark. If you have farsightedness, myopia or astigmatism and other refractive errors, you should go to the hospital for an optometry examination or to a regular professional optician to wear appropriate glasses to avoid eye strain. Do not just go to the stall or irregular optical store, not after the correct optometry, buy a pair of glasses to wear, will bring damage to the eyes. 3, life and living should be regular: control their emotions and temper, cheerful character, rest and exercise should be reasonably arranged. 4, reasonable arrangement of diet: three meals a day to ensure adequate nutrition, should eat more food rich in vitamin C, vitamin E, less greasy, too salty food, avoid smoking and alcohol, avoid overeating.