There may be a positive correlation between the severity of lung nodules and smoking, and smoking may be a risk factor for the development of lung nodules. Lung nodules are usually defined as the presence of punctate or spherical high-density lesions on imaging of the lungs. Lung nodules are usually caused by disease, such as a pathogenic bacterial infection of the lungs, or a benign or malignant tumor of the lungs. Smoking is a definite risk factor for lung cancer, and long-term excessive smoking may also cause lung infections, so it can be assumed that there is a correlation between lung nodules and smoking. The damaging effects of smoking on the lungs are well established, and patients with lung nodules are advised to always minimize or avoid smoking. In conclusion, the presence of nodules in the lungs is not necessarily due to smoking, but smoking may increase the risk of nodules in the lungs.