1. Mouth and throat
Smoke (especially the tar contained in it) is a carcinogen-that is, it will cause cancer in the tissues it touches, so any part of the smoker's respiratory tract (including the mouth and throat) may cause cancer.
2. Heart and arteries
Nicotine can make the heart beat faster and blood pressure rise. Tobacco smoke may be caused by carbon monoxide, which seems to promote the accumulation of atherosclerosis. This condition is one of the causes of many heart diseases. Heavy smokers are much more likely to die of a heart attack than non-smokers.
2. Esophagus
Most smokers like to swallow a certain amount of cigarettes, so the digestive tract (especially esophagus and pharynx) is at risk of cancer.
3. Lung
Fine hairs arranged in the airway of the lung usually exclude hydrogen foreign bodies from the lung tissue. These villi will constantly sweep the particles in the lungs into phlegm or mucus and excrete them. In addition to causing cancer, the chemicals in tobacco smoke will gradually destroy some villi and increase mucus secretion, so there are chronic diseases in the lungs and bronchitis is also prone to infection. Obviously, the "smoker's cough" is due to the impairment of the mechanical efficiency of lung cleaning, so the amount of sputum has increased.