Why Smoking Causes Shortness of Breath: Lung Damage and Reduced Oxygen Exchange

Smoking damages lungs in multiple ways:

• Airway inflammation and scarring – Lungs lose elasticity, impairing expansion/contraction.
• Alveolar destruction – Tiny air sacs responsible for oxygen transfer are damaged, reducing oxygen uptake.
• Cilia damage – Impaired mucus clearance leads to buildup, worsening breathlessness.

These changes cause dyspnea even with mild exertion. Quitting smoking is the most effective intervention.