Smoking can cause the body to lose weight, because the nicotine and tar in the smoke is harmful to the health of the body, inhaled into the trachea or absorbed by the human blood, will obviously lead to poor absorption and digestion, the intake of nutrients will relatively reduce the absorption of its nutrients, long-term smoking will lead to the body to lose weight, and secondary malnutrition. Smoking also places a significant burden and load on the cardiovascular endothelium, such as the coronary endothelium of the heart, causing the formation of atheromatous plaque, which can easily lead to coronary heart disease or strokes. It can also lead to poor digestion and absorption of food. Long-term smoking also leads to plant nerve dysfunction, and lack of rest and sleep during plant nerve dysfunction can also lead to wasting. If a smoker loses weight rapidly in a short period of time, it is recommended that a chest X-ray or chest CT examination be performed as soon as possible to rule out the occurrence of malignant tumors such as lung cancer.