Smoking causes the respiratory tract to be unobstructed and secretions to increase, leading to elevated chronic obstructive pulmonary disease and an increase in asthma and tuberculosis disease in adolescents. At the same time, tobacco contains a large number of carcinogenic substances, which can cause mutations in key genes in the organism, dysfunction of the normal growth and control mechanisms, leading to cellular cancer and the occurrence of malignant tumors, such as lung cancer, nasopharyngeal carcinoma, esophageal cancer and so on. Smoking can also induce cardiovascular and cerebrovascular diseases, is the biggest cause of coronary heart disease, can cause cerebral thrombosis, myocardial infarction and other diseases, and will even cause a decline in fertility, resulting in premature birth of the fetus and stunted development and other symptoms. In short, smoking is harmful but not beneficial, for the sake of family and personal health, it is recommended to quit smoking as soon as possible.