Even brief tobacco use changes normal lung function, but over the long term, the respiratory system suffers serious breakdown. All human cells need oxygen in order to live and grow. The rest of the body depends upon the lungs to extract oxygen from inhaled air and to send it to the heart for distribution.
When this process fails, health problems can arise elsewhere in the body. Lung diseases alone, however, are responsible for hundreds of thousands of deaths linked to cigarette smoking in the United States each year.
Emphysema
Cigarette smoking bombards the lungs with carcinogens, toxins and particulate many times a day, every day. Short-term damage to the bronchial airways prevent the cilia from properly cleaning debris from the gases entering the lungs. As the American Lung Association relates, this foreign matter causes an inflammatory response, which becomes a long-term health problem that affects lung tissue properties.
A loss of elasticity in the alveoli, or air sacs of the lungs, causes emphysema, a stage of chronic obstructive pulmonary disorder, or COPD, that follows from chronic bronchitis if tobacco use continues. Less flexibility in the alveoli mean less efficient movement of oxygen and carbon dioxide in and out of the lungs and circulating bloodstream. Emphysema greatly diminishes breathing ability. The Centers for Disease Control and Prevention list a combined annual total of COPD deaths from smoking at 92,900 for 2004.
Reduced Oxygen Transfer
Besides structural breakdown, the lungs' abilities to send the required load of oxygen to the blood and heart are hampered by carbon monoxide inhaled during cigarette smoking. The CDC notes that carbon monoxide physically binds to the hemoglobin in the blood that is supposed to carry oxygen.
In addition, blood oxygen levels may be further reduced by blood vessel health problems. The arteries and veins that serve as the lungs' pathways to and from the heart may suffer from pulmonary hypertension. This high blood pressure is produced when cholesterol deposits brought on by long-term tobacco use clog and narrow the blood vessels. The Mayo Clinic reports that this lung condition may give rise to heart failure, which can be fatal.
Lung Cancer
The CDC reports that every day spent cigarette smoking increases the risk of contracting lung cancer. On average, long-term tobacco users have 20 times the lung cancer risk of nonsmokers. This health problem is usually fatal, taking the lives of about 128,900 smokers per year, according to the CDC's 2004 data.
