Why are smokers often out of breath?

Smoking damages the lungs, which are responsible for taking in oxygen and expelling carbon dioxide. Smoking causes inflammation and scarring of the lung tissue, making it less elastic and more difficult for the lungs to expand and contract. This damage can lead to shortness of breath, even with mild exertion.

In addition, smoking also damages the tiny air sacs in the lungs called alveoli, which are responsible for transferring oxygen from the lungs into the bloodstream. This damage can further reduce the amount of oxygen that reaches the bloodstream, leading to shortness of breath.

Finally, smoking can also damage the cilia, which are tiny hairs in the lungs that help to clear out mucus and other particles. When cilia are damaged, it allows mucus to build up in the lungs, which can further worsen shortness of breath.