Why do coffee drinkers feel more clear headed after consuming caffeine? Why do some get a headache without it? Does caffeine cause any permanent brain changes and can the brain go back to ‘normal’ after years of caffeine use?
In: Biology
Contrary to popular belief, the most widespread drug addiction is caffeine, the chemical in coffee, energy drinks, tea, ect. People feel “better” after consuming because it gives them a fix for their addiction. Vice versa if they do not get their “fix” it can cause withdraw symptoms, like headaches. It does not cause permanent brain damage and after the withdrawal and detox, just like any other addiction, the brain will return back to normal.
Short answer for the first two is addiction and their body isnt used to functioning without caffeine.
Whether or not it causes a permanent change is a good question I’m not sure the answer to but I dont think thered be any drastic or permanent changes so after some time off caffeine the body would adjust back to “normal”, I wouldnt even imagine it would take years to be honest, a couple weeks or months maybe. Since caffeines water soluable I wouldnt expect it to be stored in the body and build up plus the metabolic half life of caffeine is like 2-6 hours so it doesnt take too long for it to end up getting through the system and removed from the body. Once the withdrawal symptoms (tiredness, irritability, headaches, etc.) were no longer present I’d say the person would be more or less back to “normal”.
As far as we can tell there is no long term changes done by consuming caffeine. The changes we see is mostly related to the body adapting to the caffeine by getting more tired on a normal bases. Think of it as producing anti-caffeine to negate the effects. So people who are addicted to caffeine needs caffeine to stay awake and alert. So the “correct” way to drink coffee is to only drink it when you need the extra boost to stay awake and alert but no not drink it more then maximum a couple of times a week.
Hi y’all,
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Headache is withdrawal. As a three cup a day drinker it only lasts for about a day if you stop having coffee entirely. Only other lingering effect is just maybe craving the taste / smell.
Your body has a “natural state” it likes to maintain that includes levels of chemicals called neurotransmitters and hormones. Regularly altering this with a drug will cause your body to compensate for the drug (tolerance). If you take the drug away, it will take your body time to go back to it’s natural state (withdrawal). Common side effects such as irritability, mood swings, shaking, headaches are mostly caused by neutransmitter imbalances during the time it takes your body to return to normal.
Your brain knows when it needs to sleep by measuring a chemical which builds up during the day. When you sleep, this chemical, adenosine, gets cleared out – and then once you’re awake, it builds up again, slowly. The more of it you have in your brain, the tireder you become. Then eventually you fall asleep, and your brain clears the adenosine out and resets it to zero for the next day.
Caffeine basically blocks your brain’s ability to measure this chemical. There isn’t an easy way to ELI5 this part, but your brain has these things called “receptors” which this chemical connects with, and that’s how the brain knows how much of it there is – caffeine gets in between the chemical and the receptors, preventing them from connecting together. So even though you have a bunch of this chemical in your brain because you’ve been awake for a long time (or you didn’t get enough sleep last night), caffeine falsely tricks your brain into thinking “wow, there’s basically no adenosine here at all, I must be properly well rested and not have any need for sleep right now!” This leads to a clear-headed and alert state of mind, as your brain isn’t trying to get you to wind down for sleep because it thinks you don’t need any. Think of the receptors like smoke detectors – caffeine stops them from detecting the smoke.
The reason you get a headache from withdrawal is because unfortunately, eventually your brain cottons on to the trick caffeine is playing, and it creates new receptors to measure the levels of adenosine. So it’s like “Ah, you’re blocking my receptors to stop me measuring it! No problem, I’ll make new ones, and there won’t be enough caffeine to block *all* of them”. This is why, over time, you need more caffeine in order to feel the same effects. The brain simply adjusts to the caffeine and tries to return your sleep cycle to normal. The headache arises because when you *don’t* drink caffeine, your brain falsely believes you’re a lot *more* tired than you are, because these receptors are measuring all of the adenosine in your brain – but your brain had become used to not measuring much of it at all, because the caffeine was blocking it. So now, it thinks you’re suddenly absolutely *wrecked*, because out of nowhere, it’s detecting a whole bunch of adenosine that it wasn’t detecting before.
As regards permanent changes, we don’t really know. Abstaining from caffeine for several weeks causes a “reset” of sorts – after a few weeks, your brain realises that most of the extra receptors it created are surplus to the amount of adenosine you actually have, and it starts getting rid of them again. In theory, there’s no reason why this would change over time, but it’s not fully understood or known right now, so nobody can say for sure.
This is all based on my very basic understanding of brain chemistry, so be patient and don’t @ me, scientists.
Your brain produces a chemical called adenosine, which makes you sleepy. The longer you’re awake, the more work adenosine puts in. You have adenosine receptors, which take in adenosine and make it work.
Caffeine is an “adenosine receptor antagonist.” That means that it makes your adenosine receptors stop working. This means that your brain will not take in the adenosine it produces, so when you drink coffee you stop feeling sleepy and stay awake longer. This means you’re more alert, and your motor skills are a bit tighter.
I’m not clear on even the basic science of this aspect, but caffeine also has the indirect effect of increasing the levels of dopamine (the happy chemical) in your system. This means you generally are in a better mood when you take caffeine. This is important when you think about what happens when you stop taking caffeine.
Again, I’m unclear on the science of withdrawal but after your body becomes accustomed to a certain level of chemicals, changing those levels leads to withdrawal symptoms like headaches, nausea, etc. This is “physical addiction:” your body’s negative reaction to a chemical, or the lack of a chemical.
Because caffeine is only mildly physically addictive, the nature of the addiction is physical only to a small extent. The effect is real, but the reaction to it is more of a psychological addiction. You like the way you feel when you have all this dopamine in your system, and you know that when you stop, you’re going to feel cranky, tired, sluggish and uncoordinated and have a headache. So, you drink more caffeine to avoid feeling that way. This is a roundabout way of saying that your body’s reaction to caffeine withdrawal is minor and temporary, but the psychological need to avoid those symptoms leads to continuing use.
One of the other elements that’s worth thinking about is dehydration. Most people don’t drink enough water, but some of them do drink enough coffee to prevent dehydration. If you stop drinking coffee and don’t replace it with a different drink, you’ll become dehydrated and that will give you a headache.
If you’ve been drinking coffee or anything caffeinated daily for a while, that headache you feel on days when you do without is a symptom of mild dependence on caffeine.
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