Question: how does smoking affect respiratory system since the smoke is expelled

Michael Kimwele answered on 21 Jul 2025:

Although smoke is expelled after inhalation, smoking still severely affects the respiratory system because harmful chemicals in tobacco smoke—such as tar, carbon monoxide, and formaldehyde—are absorbed into the lungs during each puff. These substances irritate and inflame the lining of the airways, damage cilia (the tiny hair-like structures that help clear mucus and debris), and penetrate deep into the alveoli where gas exchange occurs. Over time, this leads to chronic inflammation, reduced lung function, increased mucus production, and diseases like chronic bronchitis, emphysema, and lung cancer. Even brief exposure can trigger immediate negative effects, and cumulative exposure causes lasting, often irreversible damage.