The long-term consumption of betel nut or betel nut products in large quantities is harmful to the human body and may cause the development of many diseases, including oral diseases. If a pregnant woman has the habit of chewing betel nut, it may also increase the probability of miscarriage. The hazards of betel nut chewing are usually oral damage, digestive diseases, cardiovascular damage and neurotoxicity: a. Oral damage: 1, tooth loss: betel nut is tough, long-term chewing betel nut will lead to tooth loss, resulting in dental caries and pigmentation, etc.; 2, periodontal disease: betel nut juice mixed with oral calcium easy to form calculus, dental calculus exists in the periodontium, if not cleaned in time, may lead to Periodontitis, periodontal abscess and other infectious diseases; 3, oral mucosal lesions: long-term betel nut chewing can easily lead to oral mucosal lesions, such as oral mucosal white spots and fibrosis, which can lead to oral cancer in serious cases. Most oral cancer patients have a history of long-term betel nut chewing; 4, TMJ pain: because betel nut chewing often needs to increase the weight of the temporomandibular joint, so long-term betel nut chewing may lead to pain, stiffness or popping of the temporomandibular joint, and in serious cases, there may be joint disc perforation. Second, digestive diseases: betel nut alkaloids in betel nut easily affect the nervous system, the impact on the taste system, and chewing betel nut easily lead to reduced saliva secretion, resulting in indigestion. Third, cardiovascular damage: betel nut ephedrine has excitatory nerve, vasoconstrictor effect, patients with cardiovascular disease, such as myocardial ischemia patients chewing betel nut easily lead to palpitations, arrhythmia and other symptoms. Fourth, neurotoxicity: betel nut’s ephedrine effect also has a non-negligible impact on the nervous system. After taking it may lead to headache, dizziness, excitement and other phenomena, serious cases may appear poisoning phenomena, such as brain tremor. Long-term consumption has dependence or addiction.