The causes of senile cataracts are multifaceted and include both external factors and factors intrinsic to the whole body, personal constitution, and nutritional regulation. Recent studies have shown that cataracts in the elderly are part of the aging process of the human body and are due to disorders in the metabolism of lens cells and the formation of clouding. Other factors such as frequent exposure to ultraviolet rays can also affect the metabolism of the lens and cause clouding.