The fourth Sunday in September every year is International Day of the Deaf. The World Federation of the Deaf hopes that by setting up this festival, the society will pay attention to the deaf and improve the social status of the deaf.

Deafness is a common sensory system defect. There are many factors that cause deafness, mainly including genetic factors, environmental factors and other unknown factors. Among them, genetic factors play an important role.

     Deafness can be divided into four types according to different inheritance methods, autosomal dominant inheritance, autosomal recessive inheritance, X chromosome inheritance and Y chromosome inheritance.

     According to the diseased part of the deafness, it can be divided into three categories, conductive deafness, sensorineural deafness and mixed deafness. Conductive deafness is deafness caused by the sound wave conduction function of the outer ear, tympanic membrane and auditory ossicles. It can be treated by some medical methods; sensorineural deafness is deafness caused by damage to the inner ear, auditory nerve or brain, which is more common It is the abnormal structure or function of the cochlear sensory nerve epithelial hair cells. This symptom may come from acquired external trauma, ototoxic drugs or congenital abnormalities. In general, sensorineural hearing loss is difficult to cure; mixed hearing loss includes the former two deafness.

     Due to the development of modern industry, noise has also become one of people's life problems. Traffic noise, construction noise, entertainment noise, etc. affect people's lives, and even cause noise-induced deafness.

     Noise-induced hearing loss is caused by long-term exposure to noise or high-intensity sound stimulation, which is a type of sensorineural hearing loss. Generally speaking, noise above 85 decibels is hearing-impairing, and long-term exposure to this noise will cause progressive hearing loss, accompanied by tinnitus. If it is in the early stage of noise-induced deafness, this kind of hearing loss can be recovered, but if it is affected by long-term noise, it will not only cause the necrosis and apoptosis of the cochlear sensory nerve epithelial hair cells, but also cause metabolic damage and cause systemic damage. The disorder affects the life of the patient.

     Hereditary deafness is determined before birth, and most of them are difficult to change, but acquired deafness can be prevented by some methods.

     It is recommended that everyone pay attention to protect their ears, stay away from noise, and wear noise-reducing headphones; when choosing a place of residence, stay away from traffic arteries, KTVs and other high-intensity noise situations. However, it is not good that no noise is present at all. Low-intensity noise can also improve the cochlea’s tolerance to noise, so that the ears will not be caught off guard when encountering high-intensity noise.

     In addition, you can usually eat more foods rich in vitamin C, vitamin E, beta carotene, these substances help prevent noise-induced deafness.