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Smoking and respiratory health

Smoking and respiratory health

It is estimated that smoking causes some 440,000 premature deaths every year, of which about a quarter are from lung cancer and around one fifth are from chronic obstructive lung disease - bronchitis and emphysema.

The respiratory system is vital to life and anything which prevents it functioning can result in death. Often cancers of these organs are not discovered until it is too late to cure them: According to the Lung Cancer Alliance, lung cancer has a 5-year survival rate of only 15% - meaning that 85% of people who get lung cancer will die within those five years.1

Lung cancer

Lung cancer kills more people than any other type of cancer and vast majority of these deaths are caused by smoking. People who smoke are 10 to 20 times more likely to get lung cancer or die from lung cancer than people who do not smoke. The longer a person smokes and the more cigarettes smoked each day, the more risk goes up.2

Increased risk of developing lung cancer

Age at time of starting to smoke is important. The younger a person is when he or she starts smoking, the greater their risk of developing lung cancer. A US study found that smoking during the teenage years causes permanent genetic changes in the lungs and forever increases the risk of lung cancer, even if the smoker subsequently stops.3

Chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary (lung) disease (including chronic bronchitis and emphysema) is a progressively disabling disease. It can cause prolonged suffering due to difficulty in breathing because of the obstruction or narrowing of the small airways in the lung and the destruction of the lung’s air sacs due to smoking. The onset of the disease is very slow and breathlessness only becomes troublesome when about half of the lung has been destroyed. The disease is rarely reversible.

Smoking is the main cause of chronic obstructive lung disease: it is very rare in non-smokers. According to the latest World Health Organization statistics, currently 210 million people have COPD and it will become the third leading cause of death worldwide by 2030.4


Pneumonia is much more common for smokers. It was found that people who smoke more than 20 cigarettes per day were almost three times more likely to acquire pneumonia than people who never smoked.5


Cigarette smoke has been found to cause asthma both in adult smokers and in children around smokers. One study found that adults who smoke are 33% more likely to develop asthma than those who don't smoke.6 Also, according to the Global Initiative for Asthma, exposure to tobacco smoke both prenatally and after birth is associated with measurable harmful effects including a greater risk of developing asthma-like symptoms in early childhood, and infants of smoking mothers are four times more likely to develop wheezing illnesses in the first year of life.7

The benefits of stopping smoking

Quitting smoking reduces the risk of cancer and respiratory problems. Studies have shown that smokers who quit by age 30 reduce their chances of dying early from smoking by more than 90%. However, regardless of age, people who quit smoking are less likely than those who keep smoking to die from a smoking-related illness.8


1 Lung Cancer Alliance.

2 Centers for Disease Control and Prevention. Retrieved November 2, 2010.

3 Wiencke, J.K. et al. Journal of the National Cancer Institute, 1999; 91 (7): 614 – 619.

4 World Health Organization. Retrieved November 2, 2010.

5 American College Of Chest Physicians (1999, August 16). Smokers Pneumonia Risk Three Times Greater. ScienceDaily. Retrieved November 2, 2010.

6 Piipari R, Jaakkola JJ, Jaakkola N, Jaakkola MS. Smoking and asthma in adults. Eur Respir J 2004;24:734–739.

7 Global Initiative For Asthma. Global Strategy for Asthma Management and Prevention, 2009.

8 National Cancer Institute. Harm of Smoking and Health Benefits of Quitting. Retrieved November 2, 2010.

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