Editing Tobacco smoking (section)

==Consumption==

===Methods===
{{Hatnote|For more about the production of the agricultural product, see [[Cultivation of tobacco]], [[Types of tobacco]], [[Curing of tobacco]], and [[Tobacco products]]}}

[[Tobacco]] is an agricultural product processed from the fresh leaves of plants in the genus ''[[Nicotiana]]''. The genus contains several species, of which ''[[Nicotiana tabacum]]'' is the most commonly grown. ''[[Nicotiana rustica]]'' follows second, containing higher concentrations of nicotine. The leaves are harvested and cured to allow the slow [[oxidation]] and degradation of [[carotenoid]]s in tobacco leaves. This produces certain compounds in the tobacco leaves which can be attributed to sweet hay, tea, rose oil, or fruity aromatic flavors. Before packaging, the tobacco is often combined with other additives to increase the addictive potency, shift the product's [[pH]], or improve the effects of smoke by making it more palatable. In the United States these additives are regulated to [[List of additives in cigarettes|599 substances]].<ref name="WHOJeffreyWigand"/> The product is then processed, packaged, and shipped to consumer markets.

Common methods of consuming tobacco include the following:
{{multiple image
| align             = right
| direction         = vertical
| width             = 180
| image1            = Patch of Tobacco (Nicotiana tabacum ) in a field in Intercourse, Pennsylvania..jpg
| alt1              = Field of tobacco organized in rows extending to the horizon.
| caption1          = Tobacco field in [[Intercourse, Pennsylvania]]
| image2            = Basma-tobacco-drying.jpg
| alt2              = Powderly stripps hung vertically, slightly sun bleached.
| caption2          = [[Tobacco leaves|Basma]] leaves curing in the sun at [[Pomak]] village of [[Xanthi]], Thrace, Greece
| image3            = DunhillLightFlake.jpg
| alt3              = Rectangular strips stacked in an open square box.
| caption3          = Processed tobacco pressed into flakes for pipe smoking
| total_width       = 
}}

;Beedi: [[Beedi]]s are thin South Asian cigarettes filled with tobacco flakes and wrapped in a tendu leaf tied with a string at one end. They produce higher levels of carbon monoxide, nicotine, and tar than cigarettes typical in the United States.<ref>{{Cite web|url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4836a2.htm|title=Bidi Use Among Urban Youth – Massachusetts, March–April 1999|access-date=14 February 2009|date=17 September 1999|publisher=Centers for Disease Control and Prevention|archive-date=11 February 2009|archive-url=https://web.archive.org/web/20090211061406/http://www.cdc.gov/mmwr/preview/mmwrhtml/mm4836a2.htm|url-status=live}}</ref><ref>{{cite journal | last1 = Pakhale | first1 = S. M. | last2 = Maru | first2 = G. B. | title = Distribution of major and minor alkaloids in tobacco, mainstream and sidestream smoke of popular Indian smoking products | journal = Food and Chemical Toxicology | volume = 36 | issue = 12 | pages = 1131–1138 | date = Dec 1998 | pmid = 9862656 | doi = 10.1016/S0278-6915(98)00071-4 | issn = 0278-6915  }}</ref>

[[File:Diospyros melanoxylon Tendu.jpg|thumb|Tendu Patta (Leaf) collection for Beedi industries]]

;Cigars: [[Cigar]]s are tightly rolled bundles of dried and fermented tobacco that are ignited so that smoke may be drawn into the smoker's mouth. They are generally not inhaled because of the high alkalinity of the smoke, which can quickly irritate the trachea and lungs. The prevalence of cigar smoking varies depending on location, historical period, and population surveyed, and prevalence estimates vary somewhat depending on the survey method. The United States is the top consuming country by far, followed by Germany and the United Kingdom; the US and Western Europe account for about 75% of cigar sales worldwide.<ref name="Rarick">{{Cite journal|ssrn=1127582|author=Rarick CA|title=Note on the premium cigar industry|date=2 April 2008|doi=10.2139/ssrn.1127582 |s2cid=152340055 }}</ref> As of 2005 it is estimated that 4.3% of men and 0.3% of women smoke cigars in the US.<ref>{{Cite journal|journal=MMWR Morb Mortal Wkly Rep|year=2006|volume=55|issue=42|pages=1145–8|title=Tobacco use among adults—United States, 2005|vauthors=Mariolis P, Rock VJ, Asman K|url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5542a1.htm|pmid=17065979|display-authors=etal|access-date=17 September 2017|archive-date=26 September 2017|archive-url=https://web.archive.org/web/20170926235944/https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5542a1.htm|url-status=live}}</ref>

;Cigarettes: ''[[Cigarette]]s'', French for "small cigar", are a product consumed through smoking and manufactured out of cured and finely cut tobacco leaves and reconstituted tobacco, often combined with other additives, which are then rolled or stuffed into a paper-wrapped cylinder.<ref name="WHOJeffreyWigand">{{Cite web|url=http://www.jeffreywigand.com/WHOFinal.pdf|title=ADDITIVES, CIGARETTE DESIGN and TOBACCO PRODUCT REGULATION|access-date=14 February 2009|last=Wigand|first=Jeffrey S.|date=July 2006|publisher=Jeffrey Wigand|location=Mt. Pleasant, MI 48804|archive-date=16 May 2011|archive-url=https://web.archive.org/web/20110516151158/http://www.jeffreywigand.com/WHOFinal.pdf|url-status=live}}<!-- RELIABLE ONLY FOR DEFINITION OF CIGARETTE --></ref> Cigarettes are ignited and inhaled, usually through a cellulose acetate filter, into the mouth and lungs.

{{anchor|French inhale}}
;Hookah: ''[[Hookah]]'' are a single or multi-stemmed (often glass-based) water pipe for smoking. Originally from India, the hookah was a symbol of pride and honor for the landlords, kings, and other such high-class people.  Now, the hookah has gained immense popularity, especially in the Middle East. A hookah operates by water filtration and indirect heat. It can be used for smoking herbal fruits, tobacco, or [[cannabis (drug)|cannabis]].
;Kretek: ''[[Kretek]]'' are cigarettes made with a complex blend of tobacco, [[clove]]s and a flavoring "sauce". It was first introduced in the 1880s in Kudus, Java, to deliver the medicinal eugenol of cloves to the lungs. The quality and variety of tobacco play an important role in kretek production, from which kretek can contain more than 30 types of tobacco. Minced dried clove buds weighing about one-third of the tobacco blend are added to add flavoring. In 2004 the United States prohibited cigarettes from having a "characterizing flavor" of certain ingredients other than tobacco and menthol, thereby removing kretek from being classified as cigarettes.<ref>{{Cite press release|url=http://thomas.loc.gov/cgi-bin/bdquery/z?d108:SN02461:@@@D&summ2=m&|access-date=1 August 2007|publisher=Library of Congress|title=A bill to protect the public health by providing the Food and Drug Administration with certain authority to regulate tobacco products. (Summary)|date=20 May 2004|archive-date=4 September 2015|archive-url=https://web.archive.org/web/20150904081039/http://thomas.loc.gov/cgi-bin/bdquery/z?d108:SN02461:@@@D&summ2=m&|url-status=dead}}</ref>
;Pipe smoking: [[Pipe smoking]] is done with a tobacco pipe, typically consisting of a small chamber (the bowl) for the combustion of the tobacco to be smoked and a thin stem (shank) that ends in a mouthpiece (the bit). Shredded pieces of tobacco are placed into the chamber and ignited.
;Roll-your-own: [[Roll-your-own cigarette|Roll-your-own]] or hand-rolled cigarettes, often called "rollies", "cigi" or "Roll-ups", are very popular particularly in Europe. These are prepared from loose tobacco, cigarette papers, and filters all bought separately. They are usually much cheaper than ready-made cigarettes and small contraptions can be bought making the process easier.
;Vaporizer: A [[vaporizer (cannabis)|vaporizer]] is a device used to sublimate the active ingredients of plant material. Rather than burning the herb, which produces potentially irritating, toxic, or [[carcinogen]]ic by-products; a vaporizer heats the material in a partial vacuum so that the active compounds contained in the plant boil off into a vapor. This method is often preferable when medically administering the smoke substance, as opposed to directly pyrolyzing the plant material.

===Physiology===
{{See also|Chain smoking}}
[[File:Blood nicotine graph.jpg|thumb|A graph that shows the efficiency of smoking as a way to absorb nicotine compared to other forms of intake]]

The active substances in tobacco, especially cigarettes, are administered by burning the leaves and inhaling the vaporized gas that results. This quickly and effectively delivers substances into the bloodstream by [[absorption (pharmacology)|absorption]] through the [[Pulmonary alveolus|alveoli]] in the lungs. The lungs contain some 300 million alveoli, which amounts to a surface area of over 70&nbsp;m<sup>2</sup> (about the size of a tennis court). This method is not completely efficient as not all of the smoke will be inhaled, and some amount of the active substances will be lost in the process of combustion, [[pyrolysis]].<ref name="GilmanXun2004p318">{{Harvnb|Gilman|Xun|2004|p=318}}</ref> Pipe and Cigar smoke are not inhaled because of its high [[alkalinity]], which are irritating to the [[Vertebrate trachea|trachea]] and lungs. However, because of its higher alkalinity (pH 8.5) compared to cigarette smoke (pH 5.3), non-ionized nicotine is more readily absorbed through the [[mucous membranes]] in the mouth.<ref>{{cite journal | last1 = Turner | first1 = JA | last2 = Sillett | first2 = RW | last3 = McNicol | first3 = MW | title = Effect of cigar smoking on carboxyhemoglobin and plasma nicotine concentrations in primary pipe and cigar smokers and ex-cigarette smokers | journal = British Medical Journal | volume = 2 | issue = 6099 | pages = 1387–9 | year = 1977 | pmid = 589225 | pmc = 1632361 | doi = 10.1136/bmj.2.6099.1387 }}</ref> Nicotine absorption from cigar and pipe, however, is much less than that from cigarette smoke.<ref>{{cite journal | last1 = Armitage | first1 = A. K. | last2 = Turner | first2 = D. M. | title = Absorption of Nicotine in Cigarette and Cigar Smoke through the Oral Mucosa | journal = Nature | volume = 226 | issue = 5252 | pages = 1231–1232 | year = 1970 | pmid = 5422597 | doi = 10.1038/2261231a0 | bibcode = 1970Natur.226.1231A | s2cid = 4208650 }}</ref> Nicotine and cocaine activate similar patterns of neurons, which supports the existence of common [[Enzyme substrate|substrates]] among these drugs.<ref>{{cite journal | last1 = Pich | first1 = E. M. | last2 = Pagliusi | first2 = S. R. | last3 = Tessari | first3 = M. | last4 = Talabot-Ayer | first4 = D. | last5 = Hooft Van Huijsduijnen | first5 = R. | last6 = Chiamulera | first6 = C. | title = Common neural substrates for the addictive properties of nicotine and cocaine | journal = Science | volume = 275 | issue = 5296 | pages = 83–86 | year = 1997 | pmid = 8974398 | doi = 10.1126/science.275.5296.83 | s2cid = 5923174 }}</ref>

The absorbed [[nicotine]] mimics nicotinic acetylcholine which when bound to [[nicotinic acetylcholine receptor]]s prevents the reuptake of [[acetylcholine]] thereby increasing that [[neurotransmitter]] in those areas of the body.<ref name="WonnacottPMID9023878">{{cite journal | last1 = Wonnacott | first1 = S. | title = Presynaptic nicotinic ACh receptors | journal = Trends in Neurosciences | volume = 20 | issue = 2 | pages = 92–8| year = 1997 | pmid = 9023878 | doi = 10.1016/S0166-2236(96)10073-4 | s2cid = 42215860 }}</ref> These nicotinic acetylcholine receptors are located in the central nervous system and at the nerve-muscle junction of skeletal muscles; whose activity increases heart rate, alertness,<ref name="PMID2498936">{{cite journal | last1 = Parrott | first1 = A. C. | last2 = Winder | first2 = G. | title = Nicotine chewing gum (2 mg, 4 mg) and cigarette smoking: comparative effects upon vigilance and heart rate | journal = Psychopharmacology | volume = 97 | issue = 2 | pages = 257–261 | year = 1989 | pmid = 2498936 | doi = 10.1007/BF00442260 | s2cid = 4842374 }}</ref> and faster reaction times.<ref name="WesnessWarburton1997">{{cite journal | last1 = Parkin | first1 = C. | last2 = Fairweather | first2 = D. B. | last3 = Shamsi | first3 = Z. | last4 = Stanley | first4 = N. | last5 = Hindmarch | first5 = I. | title = The effects of cigarette smoking on overnight performance | journal = Psychopharmacology | volume = 136 | issue = 2 | pages = 172–178 | year = 1998 | pmid = 9551774 | doi = 10.1007/s002130050553 | s2cid = 22962937 }}</ref> Nicotine acetylcholine stimulation is not directly addictive. However, since dopamine-releasing neurons are abundant on nicotine receptors, dopamine is released; and, in the [[nucleus accumbens]], dopamine is associated with motivation causing [[reinforcing]] behavior.<ref>{{cite journal | last1 = Pontieri | first1 = F. E. | last2 = Tanda | first2 = G. | last3 = Orzi | first3 = F. | last4 = Di Chiara | first4 = G. D. | title = Effects of nicotine on the nucleus accumbens and similarity to those of addictive drugs | journal = Nature | volume = 382 | issue = 6588 | pages = 255–257 | year = 1996 | pmid = 8717040 | doi = 10.1038/382255a0 | bibcode = 1996Natur.382..255P | s2cid = 4338516 }}</ref> Dopamine increase, in the [[Prefrontal Cortex Basal Ganglia Working Memory|prefrontal cortex]], may also increase [[working memory]].<ref>{{cite journal | last1 = Guinan | first1 = M. E. | last2 = Portas | first2 = M. R. | last3 = Hill | first3 = H. R. | title = The candida precipitin test in an immunosuppressed population | journal = Cancer | volume = 43 | issue = 1 | pages = 299–302 | year = 1979 | pmid = 761168 | doi = 10.1002/1097-0142(197901)43:1<299::AID-CNCR2820430143>3.0.CO;2-D | s2cid = 45096870 }}</ref>

When tobacco is smoked, most of the nicotine is pyrolyzed. However, a dose sufficient to cause mild somatic dependency and mild to strong psychological dependency remains. There is also a formation of [[Harmala|harmane]] (an [[MAO inhibitor]]) from the acetaldehyde in tobacco smoke. This may play a role in nicotine addiction, by facilitating a dopamine release in the [[nucleus accumbens]] as a response to nicotine stimuli.<ref>{{cite journal | last1 = Talhout | first1 = R. | last2 = Opperhuizen | first2 = A. | last3 = Van Amsterdam | first3 = J. G. C. | title = Role of acetaldehyde in tobacco smoke addiction | journal = European Neuropsychopharmacology | volume = 17 | issue = 10 | pages = 627–636 | date = Oct 2007 | pmid = 17382522 | doi = 10.1016/j.euroneuro.2007.02.013 | s2cid = 25866206 | issn = 0924-977X }}</ref> Using rat studies, withdrawal after repeated exposure to nicotine results in less responsive nucleus accumbens cells, which produce dopamine responsible for [[reinforcement]].<ref>{{cite journal | last1 = Shoaib | first1 = M. | last2 = Lowe | first2 = A. | last3 = Williams | first3 = S. | title = Imaging localised dynamic changes in the nucleus accumbens following nicotine withdrawal in rats | journal = NeuroImage | volume = 22 | issue = 2 | pages = 847–854 | year = 2004 | pmid = 15193614 | doi = 10.1016/j.neuroimage.2004.01.026 | s2cid = 43544025 }}</ref>

===Demographics===
{{Main|Prevalence of tobacco use}}

{{Multiple image
| direction         = vertical
| align             = right
| image1            = Male Smoking by Country.png
| image2            = Female Smoking by Country.png
| width             = 200
| caption1          = Percentage of '''males''' smoking any tobacco product
| caption2          = Percentage of '''females''' smoking any tobacco product. Note that there is a difference between the scales used for males and the scales used for females.<ref name="MPOWER 2008 pp=267–288"/>
}}

As of 2000, smoking was practiced by around 1.22&nbsp;billion people. At current rates of 'smoker replacement' and market growth, this may reach around 1.9&nbsp;billion in 2025.<ref name="HNPGuindonBoisclair13-16">{{Cite journal|first1=G. Emmanuel|last1=Guindon|first2=David|last2=Boisclair|title=Past, current and future trends in tobacco use|url=http://www1.worldbank.org/tobacco/pdf/Guindon-Past,%20current-%20whole.pdf|access-date=22 March 2009|year=2003|publisher=The International Bank for Reconstruction and Development / The World Bank|location=Washington DC|pages=13–16|archive-url=https://web.archive.org/web/20090318003729/http://www1.worldbank.org/tobacco/pdf/Guindon-Past,%20current-%20whole.pdf|archive-date=18 March 2009|url-status=dead}}</ref>

Smoking may be up to five times more prevalent among men than women in some communities,<ref name="HNPGuindonBoisclair13-16"/> although the gender gap usually declines with younger age.<ref name="WomenTobaccoChallenges5-6">{{Cite web|url=https://www.who.int/tobacco/media/en/WomenMonograph.pdf|archive-url=https://web.archive.org/web/20031128122821/http://www.who.int/tobacco/media/en/WomenMonograph.pdf|url-status=dead|archive-date=28 November 2003|title=Women and the Tobacco Epidemic: Challenges for the 21st Century|access-date=2 January 2009|author=The World Health Organization, and the Institute for Global Tobacco Control, Johns Hopkins School of Public Health|year=2001|publisher=World Health Organization|pages=5–6}}</ref><ref name="2001SurgeonGeneralWomen47">{{Cite web|url=https://www.cdc.gov/tobacco/data_statistics/sgr/2001/|title=Surgeon General's Report—Women and Smoking|access-date=3 January 2009|year=2001|publisher=Centers for Disease Control and Prevention|page=47|archive-date=10 July 2009|archive-url=https://web.archive.org/web/20090710040912/http://www.cdc.gov/tobacco/data_statistics/sgr/2001/|url-status=live}}</ref> In some developed countries smoking rates for men have peaked and begun to decline, while for women they continue to climb.<ref>{{Cite journal|first1=Richard|last1=Peto|first2=Alan D|last2=Lopez|first3=Jillian|last3=Boreham|first4=Michael|last4=Thun|title=Mortality from Smoking in Developed Countries 1950–2000: indirect estimates from national vital statistics|url=http://www.ctsu.ox.ac.uk/~tobacco/SMK_All_PAGES.pdf|access-date=22 March 2009|year=2006|publisher=Oxford University Press|page=9|url-status=dead|archive-url=https://web.archive.org/web/20050224232603/http://www.ctsu.ox.ac.uk/~tobacco/SMK_All_PAGES.pdf|archive-date=24 February 2005}}</ref>

As of 2002, about twenty percent of young teenagers (13–15) smoked worldwide. 80,000 to 100,000 children begin smoking every day, roughly half of whom live in Asia. Half of those who start smoking in [[adolescent]] years are projected to go on to smoke for 15 to 20 years.<ref name="WHO2002FactSheet"/> As of 2019 in the United States, roughly 800,000 high school students smoke.<ref>Tobaccofreekids.org/problem/tol-s</ref>

The [[World Health Organization]] (WHO) states that "Much of the disease burden and premature mortality attributable to tobacco use disproportionately affect the poor". Of the 1.22&nbsp;billion smokers, 1&nbsp;billion of them live in developing or transitional economies. Smoking rates have leveled off or declined in the [[developed world]].<ref>{{cite journal | title = Cigarette smoking among adults and trends in smoking cessation – United States, 2008 | journal = MMWR. Morbidity and Mortality Weekly Report | volume = 58 | issue = 44 | pages = 1227–1232 | year = 2009 | pmid = 19910909 | url = https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5844a2.htm | format = Full free text | author1 = Centers for Disease Control and Prevention (CDC) | access-date = 17 September 2017 | archive-date = 16 September 2017 | archive-url = https://web.archive.org/web/20170916142331/https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5844a2.htm | url-status = live }}</ref> In the [[developing world]], however, tobacco consumption is rising by 3.4% per year as of 2002.<ref name="WHO2002FactSheet"/>

The WHO in 2004 projected 58.8&nbsp;million deaths to occur globally,<ref name="WHO2004GBD8">{{harvnb|GBD|2008|p=8}}</ref> from which 5.4&nbsp;million are tobacco-attributed,<ref>{{harvnb|GBD|2008|p=23}}</ref> and 4.9&nbsp;million as of 2007.<ref name="WHO2007FactSheet">{{Cite web|url=http://www.wpro.who.int/media_centre/fact_sheets/fs_20070529.htm|title=WHO/WPRO-Tobacco Fact sheet|access-date=1 January 2009|date=29 May 2007|publisher=World Health Organization Regional Office for the Western Pacific|url-status=dead|archive-url=https://web.archive.org/web/20090207100241/http://www.wpro.who.int/media_centre/fact_sheets/fs_20070529.htm|archive-date=7 February 2009}}</ref> As of 2002, 70% of the deaths are in developing countries.<ref name="WHO2007FactSheet"/> As of 2017, smoking causes one in ten deaths worldwide, with half of those deaths in the US, China, India and Russia.<ref>{{Cite news|url=https://www.bbc.com/news/health-39510728|title=Smoking causes one in 10 deaths worldwide, study shows|date=6 April 2017|work=BBC News|access-date=11 April 2017|language=en-GB|archive-date=10 April 2017|archive-url=https://web.archive.org/web/20170410231718/http://www.bbc.com/news/health-39510728|url-status=live}}</ref>