While smoking exacerbates existing conditions such as asthma and allergies, it also creates many other serious breathing problems. The act of smoking places stress on the airways and lungs in ways that cause both short-term and chronic health problems. Additional effects on the body from smoking cigarettes develop conditions that allow certain respiratory diseases to take hold. The U.S. Surgeon General has proven causal relationships to a number of lung diseases that both tobacco users and nonsmokers can get from exposure to smoke.
Acute and Chronic Bronchitis
Irritation of the airways, or bronchi, from smoking cigarettes occurs gradually in smokers and child nonsmokers who inhale secondhand smoke. With persistent tobacco use, the bronchi produce an inflammatory response and excess mucus, which the damaged cilia are unable to remove naturally. The result is the frequent "smoker's cough" of chronic bronchitis, which dislodges phlegm that obstructs breathing. The American Lung Association reports that this early form of chronic obstructive pulmonary disease (COPD) can be fatal, especially if left undiagnosed and untreated.
Pneumonia
Smoking cigarettes alters immune system function in ways that invite respiratory infection to cause pneumonia, according to the Mayo Clinic. Combined with the weakening of the bronchi and lungs, this immunity disorder provokes more incidences of pneumonia than normal in tobacco users and secondary smoke inhalers. The U.S. Surgeon General's 2004 report on the health problems from smoking recognizes this causal relationship between pneumonia and smoking cigarettes. The lower resistance and reduced means to fight infection that come from smoking allow pneumonia bacteria or viruses to take hold and damage lung tissue.
Emphysema
Acute and chronic inflammation via pneumonia and bronchitis can degrade lung tissue and scar the walls of the bronchi. The American Lung Association notes that these conditions give rise to emphysema, the more advanced stage of COPD.
As the lungs lose their elasticity and holes cause collapse, breathing becomes severely impaired. Medical technology has come a long way toward managing this condition, but there is no cure. Combined COPD deaths represent the fourth major cause of fatalities in the United States. Inhaling first- and second-hand smoke are known causes of emphysema, the Mayo Clinic notes.
Lung Cancer
Lung cancer was among the first health problems caused by smoking that the surgeon general revealed in 1964. It still claims nearly 160,000 lives per year, as of 2008, the American Cancer Society reports. The mechanism of carcinogenesis is complex. Factors of higher oxidative stress, lower immunity and the bombardment of more than 60 carcinogens in smoke make tobacco users unusually susceptible to lung cancer. The disease strikes those who breathe secondhand smoke, too, and most cases are fatal.
