Effects of smoking on lung health
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Smoking and Increased Risk of Lung Diseases
Smoking is strongly linked to a much higher risk of several serious lung diseases. Smokers have a greatly increased chance of developing lung cancer, with risk ratios showing more than a tenfold increase compared to non-smokers. The risk of chronic obstructive pulmonary disease (COPD) is also about four times higher in smokers, and the risk of asthma is significantly elevated as well. Smoking also increases the risk of sleep apnea, asthma attacks, and tuberculosis in both active and passive smokers 1489.
Impact of Smoking on Lung Function
Smoking causes a clear decline in lung function. Studies show that both current and former smokers have lower lung function compared to people who have never smoked. The decline is especially rapid in current smokers, particularly those who smoke heavily. However, quitting smoking can slow down this decline, and the longer someone has stopped smoking, the better their lung function tends to be 248.
Effects of Passive Smoking (Secondhand Smoke) on Lung Health
Passive smoking, or exposure to secondhand smoke, also harms lung health. It increases the risk of lung cancer in non-smokers and leads to more cases of asthma, wheezing, lower respiratory infections, and reduced lung function in children. In adults, passive smoking is linked to more respiratory symptoms, asthma, and a small but significant reduction in lung function. Workplace exposure to secondhand smoke can be especially harmful, but smoke-free policies have been shown to improve health outcomes 137810.
Smoking, Immune System, and Lung Inflammation
Smoking disrupts the immune system in the lungs. It changes the behavior of alveolar macrophages, which are important immune cells that protect the lungs. These changes make it harder for the lungs to fight off infections and repair themselves. Smoking also increases inflammation, damages lung tissue, and leads to the release of harmful enzymes that break down the structure of the lungs. This ongoing inflammation and tissue damage contribute to diseases like COPD and lung cancer 5610.
Smoking and Lung Cancer Development
Smoking is the main preventable cause of lung cancer. It affects the way lung cells grow and respond to signals, making them more likely to become cancerous. The risk is further increased in people with other lung diseases, such as COPD. Even nicotine from vaping may increase cancer risk in people with chronic lung conditions 19.
Benefits of Smoking Cessation for Lung Health
Quitting smoking at any age brings significant health benefits. It slows the decline in lung function, reduces the risk of developing lung diseases, and improves outcomes even for people who already have lung problems. Smoking cessation is one of the most effective ways to prevent and manage respiratory diseases 246.
Conclusion
Smoking, both active and passive, has severe negative effects on lung health. It increases the risk of lung cancer, COPD, asthma, and infections, and causes a decline in lung function. The immune system in the lungs is weakened, leading to more inflammation and tissue damage. Quitting smoking and reducing exposure to secondhand smoke are crucial steps for protecting lung health and preventing serious respiratory diseases.
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