Smoking tobacco is widely accepted to be one of the most harmful things a person can do to her health, and is responsible for 20 percent of all deaths in the United States. It's the leading cause of preventable disease in the U.S.. Regardless of how many cigarettes one smokes per day, it affects health at some point. Smoking tobacco introduces more than 4,000 chemicals into your body, many of which are very harmful. Among these substances are tar (a known carcinogen), nicotine (an addictive substance) and carbon monoxide, which replaces oxygen in the blood and lungs. There are many smoking-related illnesses.
Cancer
According to the American Cancer Society, cigarette smoking is the major single cause of cancer death in the United States. Many people know that smoking causes lung cancer and that it's responsible for about 90 percent of all cancer deaths. It also causes cancer in many other areas of the body, such as the throat, mouth, larynx, esophagus, bladder, liver and more. The length of time you smoke may, in part, determine how likely you are to get cancer.
Heart Disease
Heart disease is the most common cause of death among smokers. Nicotine causes cholesterol levels to rise in the blood, which can lead to blockage of coronary arteries. Over time, arteries become hardened and narrow and experience fatty buildup, a process called atherosclerosis. If you have other risk factors such as obesity, high blood pressure or high cholesterol, smoking becomes an even greater risk for developing coronary artery disease and eventually leading to a heart attack.
Chronic Obstructive Pulmonary Disease
COPD refers to several conditions that can block the airflow into the lungs and make it very difficult to breathe. Two of the most common conditions within the COPD framework are chronic bronchitis and emphysema. Chronic bronchitis causes inflammation and production of mucus--and therefore, lots of coughing. Emphysema causes breathlessness due to damage to the small air sacks in the lungs, called alveoli. Smoking is responsible for about 80 percent of all cases of COPD.
Stroke
Smoking tobacco can damage the cardiovascular system in many ways. Nicotine and carbon monoxide reduce the levels of oxygen in the blood, raise blood pressure and damage the walls of arteries--all of which increase your risk of a stroke. Smoking has been shown to more than double your chance of having a stoke.
