The Surgeon General has called smoking "the single greatest avoidable cause of disease and death." Smoking damages multiple organ systems and some of the damage is irreversible. Smokers also are plagued by chronic cough, discolorations of the teeth and fingers, and the lingering odor of tobacco.
Lung Damage
On autopsy, a smoker's lungs are covered in soot. This is from the tar the smoker inhales. The soot, which lines the small air sacs called the alveoli, impairs the exchange of oxygen and carbon dioxide.
Carcinogens in cigarettes cause lung diseases such as cancer, chronic bronchitis, pneumonia and emphysema, according to the Mayo Clinic. The carbon monoxide that smokers inhale impedes the bloods ability to carry oxygen, so a smoker is always oxygen deprived and has very little stamina.
Cardiovascular Damage
Nicotine in cigarettes damages the inner lining of the arteries, according to the Mayo Clinic. Once the lining is damaged, fatty deposits begin to coat the artery forming blockages. If the blockages become too severe, blood flow is impeded causing the cells to be deprived of oxygen and die. The coronary arteries are small vessels; blockages in these arteries can cause heart attacks. Nicotine causes vasoconstriction in arteries that are already small and blocked. Smokers often suffer poor circulation in their legs and feet. Sometimes they require amputation of a limb in order to relieve the pain caused by the poor circulation.
Brain Damage
Smoking causes strokes for the same reasons it causes heart attacks. The carotid arteries become blocked, blood flow to the brain is interrupted and a stroke occurs. Research has also linked smoking to brain function as it destroys brain cells. A common substance found in cigarettes, 4-methylnitrosamino-1-3-pyridyl-1-butanone, or NNK, promotes inflammation of the brain and decreases IQ scores, according to research published in the July 2009 issue of Journal of Neurochemistry.
