If you have been smoking for a long time, your lungs will not completely return to normal and turn white when you quit, but you can avoid further damage to your lungs by actively quitting. The damage to the lungs caused by smoking is obvious. Harmful substances contained in tobacco, such as tar and nicotine, will be deposited in the lungs during the smoking process, forming black deposits, and the longer you smoke, the more serious the black deposits will be. Even after you stop smoking, you can only reduce further aggravation, but not make your lungs white again. However, some changes do occur in the lungs after quitting smoking, for example, the smoker’s cough, phlegm, chest tightness, shortness of breath and other symptoms will be reduced, the lung function can be restored to a certain extent, but the deposits of tar and so on are usually very difficult to remove. Therefore, smokers should recognize the harm of smoking and quit in time, not only for the health of the lungs, but also for the prevention of cardiovascular and cerebrovascular diseases, breast cancer and other important significance.