Any various causes such as aging, heredity, trauma, poisoning, radiation, etc., can cause disorders of lens metabolism, resulting in clouding of lens protein degeneration, called cataract, which is mostly seen above 40 years old and increases in incidence with age. So, what do elderly people need to pay attention to in order to prevent cataracts? The following is a list of precautions for cataract prevention in the elderly. 1.Drink more water and eat less salt: When the human body is dehydrated, the normal metabolism of body fluids is disturbed, which will produce abnormal chemicals that will damage the lens and lead to cataract. 2, avoid too strong ultraviolet radiation: research shows that if the eyes are exposed to the sun for one hour more a day, the risk of cataracts increases by 10% in a year, and the risk of cataracts for outdoor workers is three times higher than that of the general population. When the sun shines strongly, it is best to wear sunglasses with UV protection when you go out. 3, supplemental vitamins: the content of vitamin C in the human eye is about 30 times higher than in the blood. As we age, the vitamin C content in the lens decreases significantly, causing lens degeneration over time and leading to cataracts. Prevention of cataract can take 100 to 200 mg of vitamin C every day, and also appropriate supplementation of glutathione, vitamin B1, B2, E and trace elements of selenium, etc. 4.Limit calorie intake: The incidence of cataract in overly obese people is about 30% higher than that of people with normal weight. Because overweight people will produce excessive C-reactive protein, this heart risk factor can also increase the incidence of cataracts.