Folic sulfonic acid, or lutein, is a carotenoid that is needed by the human body and is widely found in vegetables, fruits, flowers and other plants. For nearsighted people, lutein is able to slow down the increase of nearsightedness. Lutein is the main component of the macula in the eye, which is not produced by the human body and can only be obtained from food. Such as papaya, goji berries, pumpkin, peaches, cabbage, the content of lutein is very rich, can help the retina of the eye against ultraviolet rays, the human body to supplement a large number of lutein can maintain the durability of vision, improve the visual reaction time, thereby reducing the damage to the vision. Lutein can play a role in filtering blue light, can reduce the role of blue light damage to the macula, thereby protecting the retinal tissue to enhance vision and reduce the occurrence of cataracts.