It is internationally accepted that smoking is a major cause of COPD and that smokers have a much higher risk of developing COPD than nonsmokers. But not all smokers develop COPD, so which smokers are more likely to develop it? 1, independent of gender: a large sample of foreign population surveys found no significant differences in the incidence of COPD between male and female smokers. The incidence of COPD is higher in men than in women, which is related to the fact that there are fewer female smokers in China. 2, the occurrence of COPD is positively correlated with the time and number of smoking. Smoking index greater than 300 (smoking index = number of cigarettes per day multiplied by the number of years) the risk of disease increases sharply. 3, related to the type of smoking. The risk of COPD for cigar and pipe smokers is only I/3 of that for paper smokers, and there is no significant difference between the risk of COPD caused by filtered paper cigarettes and non-filtered paper cigarettes in male smokers, while the incidence of COPD in women is higher in the former than in the latter, contrary to that of lung cancer. Because the occurrence of lung cancer is positively correlated with the tar content of paper cigarettes, the tar content of filtered paper cigarettes is relatively low, so the incidence of lung cancer is low. The occurrence of COPD has nothing to do with tar content, as to why women who smoke filter paper cigarettes are susceptible to COPD is not yet known. 4. Related to the way of smoking. The incidence of COPD is higher in those who inhale smoke deeply into the lungs than in those who exhale it after smoking. 5, any smoking cessation measures can reduce the damage of COPD. Quitting smoking can significantly reduce the incidence of smoking-related cancer and COPD, reduce the degree of decline in lung function, and improve exercise tolerance. The rate of lung function impairment can be significantly slowed down in the first year after quitting, and then slowed down year by year, and the incidence of COPD is delayed 15 to 20 years after quitting compared to nonsmokers. Even intermittent smoking cessation can be less protective of lung function. 6, the smoker’s own factors have a great relationship with the occurrence of COPD. There is a special substance in the human body called α1-antitrypsin (α1-AT), which can resist the damage of tobacco to the human body. Unfortunately, this thing in Asian people in general congenital deficiency. 7, there are reports that n-3 polyunsaturated fatty acids in the human body have a protective effect on the occurrence of COPD. n-3 polyunsaturated fatty acids exist in the body of fish, can intervene in the body’s inflammatory response, its intake and the risk of COPD is dependent on the negative correlation (that is, eating more fish is beneficial to the treatment of COPD).