thing to say – but if we're going to talk  about it we might as well do so honestly.

Smoking creates a temporary problem  and offers an instant solution. Once  

your brain is used to nicotine,  for up to 72 hours you are itchy,  

nervous and stressed – but one drag  and instantly, you feel really good.

But it's way more than just a physical addiction.  

Smoking helps you focus at work and  is an excuse to take regular breaks,  

which is good for you mentally. It's a tool  against boredom, it suppresses your appetite,  

it makes bad moments feel less bad  and good moments better. It's social,  

fun together and a good way to make friends as  smokers always group up. Your lips are one of the  

most sensitive parts of your body and putting  something between them is deeply satisfying.

So now that we've given smoking an honest  introduction, let's smoke a cigarette together  

to see why it makes you feel so good and what  exactly happens inside your body when you do it.

The Best Worst Thing

A cigarette is dried tobacco leaves mixed  with chemicals that make it burn slowly,  

helping you to absorb nicotine, and flavours  that make the smoke less harsh. Let's light it.

Cigarette smoke is 95% gases like carbon dioxide  and water vapour. The remaining 5% are particles  

called tar and they contain the magic sauce:  carbon or nitrogen compounds filled with nicotine.

As you inhale, billions of particles  interact with everything they pass through,  

getting stuck on your throat, tongue and trachea.  Your lungs are like big inflatable sponges and  

have a filter and barrier; the cilia cells  with hair-like extensions covered by a layer  

of mucus. They trap dust or bacteria to be  swept away in a sort of dance. Tar particles  

land in the mucus and turn into a sticky brown  substance that stops the dance and paralyses  

the cilia – allowing them to get deeper  into your lungs: to the alveoli. Alveoli are  

little air sacs and here is where your actual  breathing happens. They have very thin walls,  

so that the oxygen can transfer to your  blood and carbon dioxide can leave.

Now the magic is released. Nicotine passes through  the thin walls and enters your bloodstream,  

reaching your brain so fast that it feels  instant. The positive effect arrives right away.

If your brain had a control board, smoking  would be like pressing all the buttons at once,  

releasing loads of transmitters and hormones  that affect your whole body. Epinephrine and  

cortisol make your heart beat faster and your  body ready for action. Dopamine makes you feel  

happy and relaxed and reduces your appetite.  Beta-endorphins reduce pain and stress. Nicotine  

excites and calmes you at the same time. You  become more alert and able to focus. Your  

nerves become more sensitive to pleasant  sensations, then your whole body relaxes.  

Together all of these effects just feel great.

But your brain immediately tries to return  to normal and pushes back against the effects  

of nicotine. Which is fine as long as you have  nicotine inside your blood. But once its effects  

wear off, your body is left overcompensating,  creating a massive imbalance within itself.

The more you smoke, the harder  your body tries to push back,  

which is why nicotine is so addictive:  You stop feeling like yourself without it.

It's still great, but now you  also need it just to feel normal.

If that was all smoking did,  well that would be kind of ok.

Nicotine comes with thousands of  different chemical buddies. Cadmium,  

lead, arsenic and cyanide, hydrogen  peroxide or nitrogen oxides cause  

damage wherever they end up. Carbon monoxide  reduces how much oxygen your blood can carry.

In your lungs your cilia cells struggle. It's hard to push mucus clogged up with tar  

and some of your cilia cells die. Your alveoli  are super sensitive and can't handle this sort  

of stress. A few of your tiny air sacs pop like  balloons, causing irreparable damage. Your body  

needs to get rid of all of this tar immediately!  Goblet cells pump out extra mucus to compensate,  

which makes breathing harder, so you start  coughing to get the tar and mucus out.

Your immune system activates and macrophages begin  eating up tar particles. Smokers have way more of  

these clean up cells here because their lungs are  literally full of dirt. But the nicotine makes the  

macrophages sluggish and inefficient. Worse, they  vomit chemicals that dissolve your lung tissue  

and cause tiny wounds that turn into scar tissue.  Scars in your lungs are bad if you like breathing.

Nicotine raises your heart rate while ordering  blood vessels all over your body to constrict.  

Meanwhile toxic chemicals get stuck, causing  countless tiny wounds all over your body  

that will turn into scars. Those scars  leak proteins that create random blood  

clots making your blood vessels even narrower.  Constricted and narrow vessels put a lot of  

stress on your heart muscle that has to  work much harder to keep blood flowing.

Inside your skin, the chemicals trigger  enzymes that break down collagen,  

the protein that makes your skin  elastic and smooth. This creates  

folds and wrinkles. Your skin ages  much quicker and you look older sooner.

But maybe the worst thing is what happens to your  immune system: All over your body it reacts to  

tiny wounds and activates, fighting an invisible  enemy, damaging healthy cells in the process.  

While at the same time the nicotine makes it slow  and sluggish. Worse at fighting actual diseases.

We could go on like this, but this is getting old.

In a nutshell every single one of your organs is highly stressed 

and suffers some kind of permanent damage.

Over time fats get stuck in the scars inside  blood vessels, which get narrower and narrower,  

until they start to suffocate your organs.  Your overworked heart beats even harder to  

push blood through the extra resistance and your  blood pressure rises. So hard that fluids seep  

out of blood vessels into your lungs, which  makes breathing even harder. The likelihood  

of a blood clot blocking a critical  passage in the body rises enormously,  

which can eventually cause  a heart attack or a stroke.

Almost all smokers eventually get Chronic  Obstructive Pulmonary Disease – so many of  

your alveoli are irreversibly destroyed  that you are always short of breath,  

never able to breathe freely. Once you have  it, it can only get worse, never better again.

Finally there is cancer. You get a sort  of double whammy. On the one hand you  

flood your whole system and especially your  lungs with at least 70 highly cancer-causing  

chemicals. And on the other hand you  paralyse the part of your immune system  

that kills and prevents cancer. This  is why cancer is so likely in smokers.

Ultimately, smoking is uniquely dangerous  among the things you are legally allowed to do.

The average smoker loses 10 years of life. Which means that some lose like 5 years and others more  

like 25. You don't know which one will  be you. But it cuts into your health  

span even more – making a much larger part  of your life spent being chronically sick.

Ooooof

So why don't smokers not just like, stop doing it?  

Smokers are often seen as unhinged or  without discipline which is unfair.

Nicotine is one of the most physically and  psychologically addictive substances known  

to humanity. If you ever start using it,  you'll likely struggle with it for the  

rest of your life. The physical addiction  lasts around 3 days – but the psychological  

addiction is much harder to overcome,  because you form strong habits and it's  

connected to many social cues, like hanging  out with friends or winding down from work.

The perverse thing is that almost everybody who  starts smoking starts smoking as a teenager.  

The tobacco industry has to target vulnerable  brains and get them hooked on the pleasurable  

effects of nicotine or it would go away. Today  about a billion people will light a cigarette,  

which is a lot but at least the trends are  looking good. In 2000 34% of adults were smoking,  

in 2020 it was only 23%. Still, in 2023  about 8 million people died from it.

But it's not all doom and gloom. There are many  successful strategies for quitting, we've put  

links to some in the video description. People  who stop smoking by the age of 35 on average don't  

die earlier than non-smokers. If you are older  than that, even quitting late can add years to  

your life! It's a bit like with climate change – every bit counts even if damage has already been done.

We're not the morality or health police.  You do you – but at least be aware what  

exactly you are doing and why you are doing  it – most of you watching this don't smoke,  

so, well, just maybe never try it. Smoking  only really solves a temporary problem – but  

it creates loads of permanent ones.

Good thing I never started – but it's  

not like I never do things I know  I shouldn't. Like using sketchy  

free WiFis or downloading files without  double-checking the source – cough cough.

We tried out NordVPN to relieve some of our  existential dread. Go to NordVPN.com/Kurzgesagt  

to make sure malicious websites are blocked,  webtrackers stopped and pesky ads are hidden.  

NordVPN's Threat Protection scan files during  downloads and remove malware and trackers  

automatically - and they warn you of any apps  that seem risky – I am looking at you there!

On top, NordVPN offers many more features:  Summer is travel season and NordVPN encrypts  

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NordVPN is compatible with all major  platforms and can be used on 10 devices  

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with NordVPN's 30-day money-back guarantee.

Habits can influence your life in a major way.  

They are basically hard-wired shortcuts your brain  uses to save energy and make decisions faster. 

So why not use this shortcut-method to  influence your life in a positive way? 

We created this Habit Journal to help you do  exactly that. It contains scientific explanations,  

tutorials and colorful illustrations to help  you build the habits you want in your life.

To be honest, we created it as much  for ourselves as we did for you. 

We use it in our lives to help us  implement habits like working out  

regularly, eating healthy, learning a language,  

reading more or simply actually doing  our hobbies instead of browsing reddit. 

And we also included a few tips on how to reroute  habits you want to get rid of – like smoking.

Get it now from our shop, improve  your life in a science-backed way  

and support everything we do on this channel.