Cigarette smoke contains substances that directly damage the lung tissue thereby, reducing their capacity to absorb oxygen.

Substances released by the immune system in response to cigarette smoke also destroy the lung cells.

Smoking irritates the bronchial tree in the lungs, which in turn results in the production of more mucus causing the typical smokers' cough.

As lung function declines, breathlessness begins and can eventually lead to death due to progressive breathing problems.

Bronchitis and emphysema are some of the common consequences of cigarette smoking.