Smoking does not improve human health. It actually detracts from vital functions and longevity in a number of ways. The immediate effects of cigarette smoking on the heart, lungs and immune system damage the body little by little. Prolonged smoking habits, therefore, result in chronic diseases, some which are incurable and fatal. The Office of the U.S. Surgeon General reports that these health problems shorten the lives of tobacco users by an average of 13.8 years.
Damage to the Airways
The surgeon general's 2010 report on how cigarette smoking gives rise to disease notes that inhaling smoke paralyzes the bronchial fibers that usually keep the airways healthy and clear. This part of the respiratory system is harmed daily by habitual tobacco use until permanent damage and chronic disease, such as bronchitis, develop.
Ingesting tobacco smoke also makes health problems from temporary infection more likely, including colds, flus and pneumonia. Breathing obstructions brought on by bronchitis and pneumonia can be fatal.
Lung Tissue Damage
Tobacco use causes more serious health problems in the lungs through structural damage. As the American Lung Association reports, the flexibility of lung tissue aids the movement of oxygen from the interior air sacs, or alveoli, into the bloodstream. The heart pumps this oxygenated blood to the rest of the body's cells, to fuel metabolism.
As cigarette smoking makes lung tissue more rigid, the alveoli break down and emphysema sets in. The lungs become progressively less able to transfer oxygen, inhibiting metabolism and slowly causing death.
DNA Changes and Cancer
The surgeon general reports that oxidative stress and suppressed immunity alter DNA and allow carcinogenesis to take hold at a greater rate in tobacco users. Because the dozens of carcinogens in smoke travel through the body's bloodstream, smoking-related cancers can occur at many sites.
Cancer of the blood itself, or acute myeloid leukemia, is linked to cigarette smoking. The surgeon general notes that smoking can also cause cancers of the mouth, throat, larynx, stomach, esophagus, bladder, pancreas, kidney, cervix and uterus.
Cardiovascular Changes and Heart Disease
Smoking alters heart rate, blood pressure and cholesterol levels, which produces long-range effects on the cardiovascular system. Gradually, plague forms and swelling occurs in the blood vessels, reducing circulation.
The American Heart Association reports that this condition, atherosclerosis, is the precursor to coronary heart disease. Changes in the viscosity of the blood cells encourage clotting as well. These combined health problems significantly increase smokers' risks for potentially fatal heart attack, stroke and aneurysm.
