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Here is what coffee actually does to your brain

That damn adenosine.

COFFEE WAKES YOU up in the morning and keeps you alert throughout the day, but how does its magic ingredient actually work?

Mitchell Moffit and Gregory Brown demystify the inner workings of caffeine in their latest ASAP Science video.

The first thing to know is that part of your natural tiredness comes from a molecule called adenosine, which is produced by your body while it chugs along through the day.

“While you sleep, the concentration of adenosine declines, gradually promoting wakefulness,” the video explains.

Meanwhile, the more adenosine that builds up, the sleepier you feel.

Your morning coffee is able to hijack that process because caffeine looks a lot like adenosine to your brain cells:

PastedImage-85537

Because of its similar shape, caffeine can bind to the adenosine receptors in your brain. Once the caffeine is locked into adenosine’s rightful spot though, there is no way for the adenosine to stick around — which prevents it from building up and making you sleepy.

Without the molecule that usually induces exhaustion, “our natural stimulants run wild,” Joseph Stromberg writes in Smithsonian. The result? You feel wide awake — at least for a while.

coffeebrain

But all good things must come to an end, and your brain quickly wises up to your tricks.

When the adenosine is continually blocked from binding to its receptors, your body eventually creates more receptors — which means you need even more caffeine to plug them up. This can make kicking your coffee habit increasingly difficult, and make you need more and more caffeine to stay alert.

“When you try to quit drinking coffee or miss your daily intake,” Moffit and Brown explain, “you might experience some withdrawal symptoms and feel more tired than you would have before you ever drank coffee.”

But caffeine does more than just block adenosine. It can also pump up your levels of adrenaline and boost your mood — “the exact same thing cocaine does, just to a lesser degree,” the video says.

Watch the full ASAP Science video below.

AsapSCIENCE / YouTube

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    Mute Phillip Smyth
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    Mar 1st 2025, 10:18 PM

    He is alive and well and living in the White House under another guise.

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    Mute Daniel Skelton
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    Mar 1st 2025, 10:41 PM

    @Phillip Smyth: Don’t say that ffs, you’ll summon the incell Johnny 40 accounts (or whatever his name is)

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    Mute Bert Carolan
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    Mar 1st 2025, 11:11 PM

    @Daniel Skelton: That’s what it’s like alright.

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    Mute Fionn Bohane
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    Mar 2nd 2025, 12:57 AM

    @Phillip Smyth: That’s a very unfair comparison on ogre’s

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    Mute Brian Dunne
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    Mar 2nd 2025, 12:04 AM

    I could listen to John Lithgows voice all day!

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    Mute Basildon Joe
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    Mar 2nd 2025, 9:52 AM

    @Brian Dunne: what is this shitting mess a quiz on kids tv a load of bollox what about adult news?

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    Mute Tasty k
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    Mar 2nd 2025, 2:50 AM

    9/10 = too much

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    Mute Regular John
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    Mar 3rd 2025, 9:55 AM

    @Tasty k:
    Same, got the year for Shrek receiving the star wrong.

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    Mute Phillip Smyth
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    Mar 1st 2025, 11:33 PM

    He gave them Javelins they were surplus to requirements and not used, what a spoofer, he will never be a Roosevelt if it comes to war, at least this time we have Germany with us.

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    Mute Basildon Joe
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    Mar 2nd 2025, 9:53 AM

    @Phillip Smyth: uk leading the war as always don’t worry we will save Ireland but you need to pay the apple money

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    Mute Del Ray
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    Mar 1st 2025, 11:05 PM

    I appreciate Shreks important but still an unusual Saturday news focus given Ukraine. The coverage of the meeting in London with Zelensky is headlines elsewhere. See RTE or BBC.

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    Mute Bert Carolan
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    Mar 1st 2025, 11:12 PM

    @J B: What are you on about?

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    Mute Bert Carolan
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    Mar 1st 2025, 11:57 PM

    @J B: Great answer Einstein.

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    Mute nollaig o cellaigh
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    Mar 1st 2025, 10:10 PM

    7/10. Stupid not knowing that characters name and 2 other answers

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    Mute Oh Mammy
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    Mar 1st 2025, 10:19 PM

    Really? He played for United

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    Mute Pól Pot
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    Mar 2nd 2025, 6:51 AM

    @Oh Mammy: Wasn’t Shrek. That was a balloon with a Weetabix crushed on top.

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    Mute Alex Marquis
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    Mar 2nd 2025, 7:47 PM

    @Oh Mammy: and like a lot of very talented players, he turned out to be a very unconvincing gaffer for Derby, Birmingham City and Plymouth Argyle.

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    Mute offside again
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    Mar 1st 2025, 10:04 PM

    What ? Nothing ! Have I missed something ?

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    Mute Alex Marquis
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    Mar 2nd 2025, 7:38 PM

    He enjoyed a lot of success as a forward for club and country and was briefly England’s leading goal scorer before being overtaken by Harry Kane.

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    Mute Brian D'Arcy
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    Mar 2nd 2025, 3:51 PM

    France and Britain, colonialists supreme, divvying up the minerals of Ukraine for themselves. What a pointless war.

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    Mute Johnny Wilson
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    Mar 2nd 2025, 11:13 AM

    Didn’t the Gardai arrest a bunch of Provos with his posters in a van?

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    Mute Ray Grogan
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    Mar 2nd 2025, 7:07 PM

    I’d say he’d leave some shite behind him

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