How It Works - UK (2020-05)

034 How It Works

SCIENCE

wdamagingcana singlecigarettebe?

n 2017 the NHS found that 77,800 deaths were

ttributed to smoking, with a further 489,300

eople admitted to hospital. As an efficient

rug-deliver y system, cigarettes are designed to

acilitate the transport of addictive and

opamine-inducing chemicals such as nicotine

ntothe smoker's bloodstream. For example, the

verage smoker inhales bet ween one to t wo

milligrams of nicotine per cigarette. Nicotine is

hedriv ing force of smoking addiction, with

mokers pursuing an apparently stress-relieving

hotof dopamine. With the average person

aking ten puffs on a cigarette before it’s burnt

ut,a single pack of 20 cigarettes will provide

bout 200 hitsofnicotine.

Otherthantheaddictivenatureofnicotinea

the problem

Tobacco(Nicotianatabacum), nativeto

bothNorthandSouthAmerica,is now

oneofthemostcultivatedplantsaround

theworld.Chinais theleadingproducer

oftobacco,farmingalmost2.3million

tonnesoftheplantin2017.Betweenthe

farmlandandfingertips,harvested

tobaccogoesthroughdifferentmethods

ofcuringanddryingtocreatethetea-like

fillerfoundincigarettes.Forexample,

onemethodusedinVirginiais flue-curing

tobacco.Thisinvolveshangingpicked

leavesinsidea smallenclosedbarn,

whichis heatedbyburningdifferent

woodsandcharcoalandvented.Curing

transformstheonce-lushgreenleaves

intoshrivelledyellow-browndriedleaves

infourtoeightdays,readytobe

processedandplacedintocigarettes.

Tobaccoplantsaregrowninvastgrovesbefore

headingtoheatedbarnstodryout

hair-like cells called cilia which are responsible

for trapping pollutants and dust before they’re

absorbed by the body. As the tar builds, these

cellular bodyguards become paralysed and

unable to repel any unwanted intruders, leaving

the body at risk of infection and opening a

gateway to a collection of toxic chemicals. As the

tar continues to accumulate, a once-healthy pink

lung eventually becomes grey or black.

As one of the hundreds of smoke-bound toxins

that can enter the body, the potential damage

this deadly cocktail can cause is vast. Smoking

causes 84 per cent of deaths from lung cancer

and 83 per cent of deaths from chronic

obstructivepulmonar ydisease.Butthelungs

aren’ttheonlyorgantobeaffectedbysmoking

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Currently around 17 per cent of men in the UK are
smokers, whereas women smokers account for 13
per cent of the population

© Getty

Otherthantheaddictivenatureofnicotine,a

nglecigarettecontainsover7,000chemicals,of

whichatleast 69 areknow ntocausecancer.One

articularlydestructivetoxinisa residuecalled

ar. Uponi n ha l i ngthesmokeofburningtobacco,

hisbrownsludge entersthelungs,coatingthe

ningoftheorganalongwiththewallsofthe

achea. Along these internal walls aretiny

Whatmakessmokerscravenicotineand

whyis it sodifficulttogiveup?

Dissecting

addiction

aren ttheonlyorgantobeaffectedbysmoking.

Infact,nearlyeveryaspectofthehumanbody

canbenegativelyimpactedbysmoking. From

increasingbloodpressureandgreyingskinto

causinga strokeandinfertility, aslittleasone

cigarettea dayisenough toincreasea man’srisk

ofdevelopingheartdiseaseby 48 percent,and a

25 per centhigher risk of hav ing a stroke.

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© Illustration by The Art Agency/Barry Crouche

r

Neuron

Nicotineinteractswithyourbrain

cells,calledneurons,whichsend

messagesaroundthebrainto

signalthereleaseofhormones,

forexample.

Nicotine

Thisstimulantalkaloidis

foundin thenightshade

familyofplants,

includingtobacco.

Stubbedout

Oncea cigaretteis finished,receptors

arenolongerstimulatedbynicotine

andreturntonormalfunction.

Firstdrag

Withinthefirstsevensecondsofinhaling

smoke,nicotinereachesthebrainandbinds

withneuronreceptors,openingthemupto

generatea signalcalledanactionpotential.

Craving

Withoutanynicotinein thebloodstream,neuron

receptorsoperateasnormalbyrespondingto

neurotransmitterssuchasacetylcholine.

NEURON

RECEPTOR

NICOTINE

NEUROTRANSMITTER