According to the American Heart Association (AHA), nicotine is a highly addictive drug. Nicotine causes changes in brain chemistry that are both physically and psychologically addictive. Tobacco can be ingested in two main ways: by chewing or smoking. Tobacco use has multiple effects on the body. The American Lung Association (ALA) reports that smoking tobacco alone causes more than 393,000 deaths each year.
Cardiovascular Disease
The AHA reports that 135,000 deaths each year are due to cardiovascular (heart) disease caused by smoking cigarettes. Furthermore, heart disease is also caused by chewing tobacco, because nicotine itself in tobacco products has negative effects on the body's cardiovascular system. According to the AHA, nicotine causes short-term increases in blood pressure, heart rate, and blood flow through the heart. Over time, these can contribute to heart disease. Furthermore, the carbon monoxide in cigarette smoke causes artery damage, resulting in fatty buildup in the arteries. Fatty buildup leads to increased blood pressure, which over time leads to cardiovascular disease.
Cancer
Both smoking and chewing tobacco have the potential to cause cancer. In fact, the ALA reports that cigarette smoke contains 4,800 chemicals, 69 of which are known to cause cancer. Also according the the ALA, smoking cigarettes causes 90 percent of deaths from lung cancer. MedlinePlus reports that chewing tobacco also causes cancer: cancer of the mouth. They also report that chewing tobacco may be linked to other types of cancer as well.
Tissue Damage
Both smoking and chewing tobacco can cause tissue damage in many different organs of the body. The ALA describes how smoking tobacco can cause chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis and emphysema. In chronic bronchitis, the airways are chronically swollen, and the cells of the lung produce an excess of mucus. The swelling and mucus reduce the space in the airway for air to travel into the lungs, making it difficult to breath. Emphysema occurs when the normally elastic tissues of the lung become stretched out, and do not contract and expand normally. This makes it difficult for oxygen to be properly exchanged in the lungs, also making breathing difficult.
Chewing tobacco can also cause tissue damage. MedlinePlus reports that chewing tobacco causes decay of tooth roots, gum disease and mouth sores.
