Not everyone has lung nodules, some healthy people, some smoking, inhalation of physical and chemical foreign bodies, silicosis, lung infections, lung tumors and other people can form lung nodules. 1. Some healthy people: Some healthy people can find physiologic lung nodules, such as lymph nodes in the lungs, when they undergo chest X-ray or lung CT examination. 2. Some smokers and inhalers of physical and chemical foreign bodies: bronchial tubes and lungs can be stimulated by physical and chemical factors such as smoking and environmental pollution and form pulmonary nodules. 3. Silicosis: people who are engaged in mining minerals or occupations with dusty working environments can inhale dust and cause small nodules in the lungs. 4. Lung infections: Inflammatory granulomas caused by bacterial, fungal or viral infections in the lungs may lead to the formation of lung nodules. 5. Lung tumor: benign and malignant tumors of the lungs with small size can also be manifested as small nodules in CT examination. Different causes of pulmonary nodules may have different imaging manifestations, clinical symptoms may also be different, if you have pulmonary nodules, you need to go to the hospital to actively find out the causes, avoid blindly self-medication.