Smoking

Smoking Tobacco use - smoking and smokeless tobacco Tobacco is a plant grown for its leaves, which are smoked, chewed, or sniffed for a variety of effects. It is considered an addictive substance because it contains the chemical nicotine. The tobacco plant is believed to have originated in the Western Hemisphere. The cultivated species most often grown for North American and European tobacco products is Nicotiana tabacum. The leaves of the plant are prepared for smoking, chewing, or sniffing. In addition to nicotine, tobacco contains over 19 known carcinogens (most are collectively known as "tar") and more than 4,000 chemicals. Prior to European influence in the Americas, tobacco was used by the Indians of Mexico and Peru for ceremonies, medicinal purposes, and to alleviate hunger pangs during famines. Columbus is credited with introducing tobacco into Europe. Tobacco use became widely accepted by the Portuguese, Spanish, French, British, and Scandinavians. Explorers and sailors who became dependent upon tobacco began planting seeds at their ports of call, introducing the product into other parts of Europe and Asia. The colonists introduced tobacco on the American continent in the early 1600s. It became a major crop and trading commodity of the Jamestown colony. Over tobacco, smoking, quitting, nicotine, risk, quit, within, health, smokeless, lung, increases, effects, cancer, blood, products, death, upon, smoke, risks, people, over, normal, heart, been, years, success, specific, smokers, respiratory, rate, increased, include, disease, about, sudden