Geriatric cataract, or age-related cataract, is a clouding of the lens that begins to occur in middle and old age, with a significantly higher prevalence as age increases. Because it occurs mainly in the elderly, it used to be called senile cataract. As far as we know, the onset of senile cataract may be related to the following factors: 1. Sunlight and ultraviolet light: For many years, it has been noted that sunlight is involved in the formation of human cataracts. Under the influence of UV light, phosphorus ions may combine with calcium ions in the aging lens to form insoluble calcium phosphate, which leads to the hardening and calcification of the crystal. At the same time, ultraviolet light also affects the redox process of the lens, prompting the denaturation of lens proteins and causing cataracts. 2.Oxygen deficiency: In the case of oxygen deficiency, it can increase sodium and calcium in the crystal, reduce potassium and vitamin C accordingly, and increase lactic acid, prompting the formation of cataract. 3.Nutrient metabolism: Through animal observation, it is found that certain vitamin and trace element deficiencies are related to cataract formation, such as calcium, phosphorus, vitamin E, A, B2, etc. 4.Sclerotic dehydration: When dehydration occurs in human body, the fluid metabolism in the body is disturbed, and some abnormal substances will be produced to damage the crystal. Animal experiments prove that after giving hypertonic dehydration, the crystals appear empty. 5.Outside temperature: Foreign scholars census the incidence of cataract in workers over 60 years old who work under high temperature is significantly higher. 6, endocrine: endocrine disorders can contribute to cataracts, as illustrated by the higher occurrence of cataracts in diabetic patients compared to the general population.