1, quit smoking 20 minutes, blood pressure, heart rate, peripheral circulation improved; 2, quit smoking 24 hours, carbon monoxide levels reduced; 3, quit smoking 48 hours, taste and smell function improved; 4, quit smoking 2-12 weeks, lung function improved 30%; 5, quit smoking 3-9 months, shortness of breath, cough, cough sputum reduced; 6, quit smoking 1 year, myocardial infarction decreased 50%; 7, quit smoking 10 years, lung cancer risk decreased 50%; 8, quit smoking 15 years, the risk of myocardial infarction and stroke reduced to the level of non-smokers; 65 years old quit smoking people life expectancy than smokers 4 years longer.