The eye is a dense sphere, but there is a weak area at the back of this sphere with many sieve holes, anatomically called the sieve plate. Optic nerve fibers are divided into bundles that pass through the sieve holes into the wall of the eye and are distributed on the posterior surface of the eye to perceive light stimuli. Once the intraocular pressure exceeds its tolerance, the sieve plate becomes deformed and concave, causing apoptosis (death) of the retinal nerve fibers that “traverse” it, leading to glaucoma. Retinal nerve fibers are distributed in the plane of the posterior wall of the eye and have a positional correspondence with light. However, when a retinal nerve fiber is damaged, the area it is “responsible” for becomes invisible, which is called a dark spot. Because glaucoma is neither painful nor itchy, it is difficult for patients to detect in the early stages. These dark spots expand to form a large dark area, and a careful patient will notice a dark shadow in front of his or her eyes, which is actually a visual field defect caused by glaucoma. Patients should seek medical attention as soon as possible, otherwise the condition continues to progress and eventually leads to severe visual impairment. The sieve plate is made up of collagen, these collagen is not the same for everyone, some people have thicker collagen fibers, strong ability to withstand pressure, the eye pressure is not easily deformed, this part of the people are not allowed to get glaucoma, even if you get the disease, the lesions are relatively light. Therefore, the consciousness to eat more coarse fiber foods, such as: raw radish, groundnuts, apples and other foods containing more coarse fiber will help prevent glaucoma, as well as the progression of glaucoma. I personally noticed that before mankind achieved industrialization, food was coarser than now, with more coarse fiber content, and the prevalence of normal intraocular pressure glaucoma was much lower then than now. History books about glaucoma in our ancient times are also very rare. In addition to the difficulty in recording the way, it is not unrelated to the low prevalence of glaucoma at that time. Another example is that the Japanese have a fine diet and the prevalence of normal eye pressure glaucoma is much higher in the Japanese than in the rest of the world. The so-called normal intraocular pressure glaucoma is when the intraocular pressure is still within the normal range and the patient’s sieve plate has been deformed by pressure, resulting in glaucoma.