Long-term effects

Many of the long-term effects of smoking are felt in the respiratory system. Cigarette smoke irritates the lining of the breathing tubes (bronchi and bronchioles), which can lead to chronic bronchitis. The symptoms of this typically include shortness of breath, chest pain and a productive cough.

The tar in cigarette smoke can coat the inside of the alveoli, breaking down their structure and reducing the surface area available for gaseous exchange. This can progress to emphysema, which causes sufferers to feel breathless. Emphysema and chronic bronchitis fall under the umbrella term chronic obstructive pulmonary disease (COPD).

Tar – and many of the other chemicals in cigarette – can cause cancer, not just in the lungs, but in the other parts of the respiratory system such as the throat and mouth. Tar can also affect other parts of the body, such as the kidneys and liver and, as cancer does, it can spread.

Other long-term effects of smoking include:

• Cardiovascular disorders
• Decreased fertility and sexual function
• Gastrointestinal ulcers
• Mental health problems
• Brittle bones (osteoporosis)
• Premature skin ageing.