History of Use
Nicotine was named for the tobacco plant Nicotiana tabacum, which itself was named for Jean Nicot de Villemain, a French ambassador, who imported the plant to Portugal in 1560 as a medicine. The colony of Jamestown, Virginia, began to cultivate tobacco on a large scale around 1616. Starting in 1617, exports rose from 20,000 pounds to 1.5 million by 1629.
What had been characterized as a detestable weed soon began to be used by the English, who were told that the tobacco would improve their health. The colonists abandoned other ventures to cultivate tobacco, drawing about forty-six hundred new colonists from Europe in about fifteen years, flooding onto lands that the Powhatans had used to grow food and hunt game.
The smoking or chewing of tobacco became popular for centuries. Until the 1950s, many university lecture halls were built with ashtrays. Indoor smoking was widely accepted. The newsroom of the New York Times, for example, was used by so many chain smokers in the 1930s that by the end of each work day janitors swept away cigarette butts with pushbrooms.
The US surgeon general in 1963 issued a detailed report that associated the use of tobacco with many health problems, including heart disease, stroke, and cancer. Since then, even the inhalation of tobacco smoke from other people’s lungs (secondhand or passive smoking) has been associated with health risks.
The nicotine itself usually does not cause health risks. Most of the physical damage is caused by other substances, including tar and various chemicals. In 2013, about 17.8 percent of adults in the United States still smoked cigarettes, according to the Centers for Disease Control and Prevention. In the same year, a survey conducted by the Substance Abuse and Mental Health Administration found that 13.4 million people smoked cigars, 2.5 million people smoked tobacco in pipes, and 9 million people used smokeless or spit tobacco.
Effects and Potential Risks
The human body receives nicotine (and other addictive substances) through acetylcholine receptors in the brain, increasing the levels of neurotransmitters that regulate mood and behavior. The use of nicotine provides a shot of dopamine
, a neurotransmitter that briefly produces a sense of euphoria and relaxation, rewarding continued use and thus reinforcing addiction. The use of nicotine also increases the flow of the stimulating hormone adrenaline (epinephrine). Nicotine also increases heart rate by about twenty beats per minute, elevating blood pressure and constricting arteries.
Burning tobacco contains a minimum of sixty cancer-causing chemicals. According to the American Cancer Society in 2014, the smoking of tobacco plays a role in about 87 percent of lung-cancer cases in men and 70 percent in women, as well as many cases of emphysema and chronic bronchitis; it also aggravates asthma. Inhalation of burning tobacco also provokes cancers of the esophagus, larynx, mouth, and throat (pharynx). It also negatively affects the stomach, pancreas, kidneys, bladder, cervix, stomach, and other parts of the body, and it can increase the risk of infertility and impotence.
The use of tobacco at a young age increases the likelihood of serious addiction. Dependence becomes slightly more intense each time the drug is used. Thus, while going without the drug is easier for younger people, the addiction becomes more trenchant with age. Going without nicotine causes withdrawal symptoms (such as irritability and anxiety) that vary in intensity and duration among different users.
Other symptoms of nicotine withdrawal include difficulty concentrating, restlessness, a depressed mood, frustration, anger, hunger, occasional insomnia, and constipation or diarrhea. The use of tobacco even after onset of serious health problems is a sign of serious addiction. Some people continue using tobacco even after lung-cancer surgery, and some people defend their “freedom” to be addicted.
Although nicotine addiction is physiological, it also involves psychological cues. The desire experienced by smokers to raise their nicotine levels is often associated with daily rituals, including a cup of morning coffee, free time between work tasks, or an evening over drinks at a familiar bar. Meeting with friends (especially those who smoke) also can intensify the urge. Smoking also can be associated with specific sites, or a ride in a familiar automobile. Psychological stress can raise anxiety levels and increase the desire to smoke. Smelling burning tobacco also may increase a smoker’s desire to use the substance.
People who experience schizophrenia, depression, or other mental illnesses are more likely to smoke tobacco than those without such illnesses. Abusers of alcohol and illegal drugs also use tobacco at higher rates. Nicotine has been studied as a treatment for attention deficit hyperactivity disorder, Parkinson’s disease, and schizophrenia. Products meant to aid smokers in quitting have become a worldwide industry on which several billion dollars are spent each year. Additionally, several states have passed laws that ban smoking in public venues in an effort to decrease exposure to secondhand smoke.
Bibliography
Benowitz, Neal L., ed. Nicotine Safety and Toxicity. New York: Oxford UP, 1998. Print.
Bock, Gregory, and Jamie Goode, eds. Understanding Nicotine and Tobacco Addiction. Hoboken: Wiley, 2006. Print.
"How Many People Use Tobacco?" American Cancer Society. Amer. Cancer Soc., 13 Feb. 2014. Web. 27 Oct. 2015.
Kozlowski, Lynn T., Jack E. Henningfield, and Janet Brigham. Cigarettes, Nicotine, and Health: A Biobehavioral Approach. Thousand Oaks: Sage, 2001. Print.
"Smoking and Tobacco Use: Fast Facts." Centers for Disease Control and Prevention. CDC, 15 Apr. 2015. Web. 27 Oct. 2015.
Wagner, Eric F., ed. Nicotine Addiction among Adolescents. New York: Haworth, 2000. Print.
No comments:
Post a Comment