Astigmatism is mainly caused by congenital genes and acquired eye diseases. Generally speaking, once astigmatism is formed, it cannot be recovered. Some acquired astigmatism can be prevented: 1, long-term poor eye posture (often squinting, eye rubbing, lying down to read, etc.), for example, some people with eye discomfort, allergies and itchy eyes, will vigorously rub, rubbing eyes usually closed eyes, when the eye will move up, rubbing the pressure will be gathered in the lower part of the eye, resulting in changes in the curvature of the cornea below. When the curvature of the cornea is uneven, astigmatism will occur. Therefore, you should develop good eye habits, do not rub your eyes, do not squint to see things, do not lie down to read; intermittent eye use: after every half hour of close eye use, rest for about 10 minutes or look into the distance; reasonable diet, do more outdoor activities, regular eye examination and health care. 2, eyelid long needle eye or chalazion, so that the eyelid pressure on the cornea will also make the corneal curvature change, astigmatism and increase the astigmatism. Therefore, it is important to pay attention to eye hygiene, not to touch the eyes with dirty hands, and to avoid infections of the eyelid lid gland mouth. In summary, some cases of acquired astigmatism can be prevented by good eye care habits, but once astigmatism is formed, it usually does not recover naturally.