Tobacco smoke contains more than 4,000 chemicals, many of which are toxic and harmful. These substances can reach the deep alveoli of the lungs with tobacco smoke and are quickly absorbed by the body and are harmful to health. Passive smoking means that nonsmokers inhale the smoke exhaled by smokers and the smoke from burning cigarettes, also known as secondhand smoke. Both smoking and passive smoking can cause a variety of diseases. 1, smoking and passive smoking can lead to a variety of cancers: it has now been determined that more than sixty chemicals in tobacco smoke are carcinogenic and can lead to lung cancer, oral cancer, throat cancer, esophageal cancer, stomach cancer, pancreatic cancer, kidney cancer, bladder cancer, hemophilia, cervical cancer, etc. Compared to nonsmokers, smokers have a 6 to 13 times higher risk of dying from lung cancer, a 1 times higher risk of dying from bladder cancer, and a 3 times higher risk of dying from esophageal cancer. 2, smoking and passive smoking can cause a variety of cardiovascular diseases: smoking and passive smoking can cause coronary heart disease, stroke and so on. Some studies have shown that the risk of death from coronary heart disease in smokers is two times higher than in non-smokers, and the risk of death from stroke is two to four times higher than in non-smokers. In addition, smoking can also cause other cardiovascular diseases such as abdominal aortic aneurysm. 3, smoking and passive smoking can cause a variety of respiratory diseases: these diseases include dyspnea, chronic bronchitis, chronic obstructive pulmonary disease (LBP), etc. Smokers have 12 to 13 times the risk of developing slow-onset lung than nonsmokers. Passive smoking can significantly increase the risk of asthma and respiratory infections in children. 4, smoking and passive smoking can damage almost all organs in the body: smoking and passive smoking can cause organ damage, which can lead to infertility, low birth weight and sudden death, cataracts, erectile dysfunction in men, osteoporosis, peptic ulcers, etc.