Quitting caffeine after decades of use was a bit of a mixed bag for me in the short term, but positive in the long term.

Going caffeine-free made it much easier to lose weight as I have far less cravings for high carbs and sugar now, presumably this is related to the impulsivity impact talked about in the paper.

Going caffeine-free also made me very depressed for a while with severe anhedonia, this lasted way longer (like 3-4 months) than one would generally expect for caffeine withdrawal symptoms.

I had seemingly become so used to the increased dopamine signaling while buzzed on caffeine that my brain was a mess for a rather extended period of time as it got used to not having it.

Overall I view quitting as a positive for me, but I'd warn anyone thinking about doing it to do it carefully and closely monitor their mental health. AFAIK the impacts of quitting can be quite different for different people, so my experience may differ than that of others, but I had no idea how much of a (temporary) mental health crash quitting caffeine could cause until I experienced it.

I've had the same experience. Caffeine is super addicting, the ritual & habits surrounding it is a potent pull. For myself, it makes me erratic, impulsive, more reactive and agitated. One cup a day puts me on edge, makes me sweat more, makes me more intolerant, makes everything feel too slow. It such a sneaky drug and it can really get under your skin without you realizing how much it changes you.

After habitually consuming coffee daily in large quantities for two decades, I had mental health incident, during which I drank twice the amount of coffee and it felt like water. After that incident I still drink previous amount of coffee, but feel much better, much more rested, on an upward trajectory and like I have finally managed to escape the swamp I dragged myself into over many years.

After reevaluating your comment and my experience I declare that coffee is not always a cause of mental health incidents, sometimes it might help people.

This happened to me with Pepsi cola.

But then I found out I can drink coffee just fine, even 5 cups per day.

Now I'm thinking it was the artificial sweetener.

Agree, I drink it a lot and then stop drinking it at least once a year for a few weeks, and for sure it's a different mode of mind, but can't really qualify it besides that I remember my thinking being softer, calmer and perhaps even "more correct" without coffee.

(But I never had any mental-health incidents, and I drink a lot of it, more than all people that I personally know.)

Coffee is a plant demon that created the western civilization as we know it today...

Notably, the article is looking at coffee, both caffeinated and decaffeinated. There is a lot more to coffee than just caffeine...

Yes, same here. I have schizoaffective disorder and realizing that caffeine affected my mental health so drastically was the beginning of my recovery journey 30 years ago. I can use caffeine now as a drug when I need it. Same with alcohol.

I do believe a lot of it boils down to tolerance. I for example feel basically 0 effects, and drink it just because I like the taste (of a good one with milk, or exceptionally some good espresso / ristretto after big dinner).

I recently traveled and didn't have coffee for more than a week. No change I could feel, no craving, nothing. But one of my ex-gf was quite sensitive on many things, had frequent headaches, low blood pressure and coffee was helping with those visibly. So YMMV.

How do you know that caffeine was the cause?

It does not sound like an outcome that big coffee paid for it to be so:

Behaviourally, coffee drinkers exhibited greater impulsivity and emotional reactivity, whereas non-coffee drinkers demonstrated better memory performance.

Every damn time, for chocolate, coffee, and red wine "studies."

I agree. I'm deep into specialty coffee and I love making and drinking coffee a lot, but three cups is already higher than what I drink on a normal day. Also, most of the time when I go above this threshold, I drink decaf.

Are the Irish unique when it comes to metabolizing coffee?

I drink a small cup in the morning (like 250 ml) and 1-2 Moka pot espressos (like one shot). This typically happens between 7-10am. No more coffee after that most of the time. I like to keep it in the morning routine with breakfast. Green tea and water in my afternoons.

Personally, I don't feel any kind of "drug like" effects from this routine. I wonder about the strength of coffee people are drinking and the effects of drinking throughout the day rather than just the morning.

Anecdotally, during grad school I drank more per serving and throughout the day, and I certainly felt quite different than my current routine.

Like most things, I think people need to find some moderation/balance.

This study is Irish, so I think they likely use 170ml cups? That means a normal mug of ~500ml is 3 cups.

Perhaps they even use US coffee cup size, which is 118ml?

Honestly, using an unit of measurement that varies from 118ml to 250ml in a scientific paper brings the whole paper into question.

I do 6-10 espresso cups per day, so 3-5 does sound very moderate.

That doesn't seem even remotely surprising to me. Much of the readership here likely consumes inadvisable quantities of caffeine nearly every day and one of the most common side effects is anxiety followed closely by a number of other emotional perturbations.

In 1995, NASA did spiders experiment. Caffeine is a siginificant impulsivity trigger. :)

https://rarehistoricalphotos.com/nasa-spiders-drugs-experime...

> They didn’t test caffeine in isolation

But they did test both caffeinated and uncaffeinated coffee, and found the same effects in both, indicating that the effect is caused by something in coffee other than the caffeine

What kind of decaf coffee do you drink? There are differences between the cheap chemical Methylene way to create decaf coffee and the expensive co2 way to get rid of the caffeine.

https://cleanlabelproject.org/wp-content/uploads/CLP-Decaf-C...

That's normalising clean-ness (i.e. the state of being free of all psychoactive chemicals) perhaps too much.

The original humans adapted to a wide range of diets across the world (one reason why we're such a successful species), but most groups seem to consume mild psychoactives a lot (it's hard not to, so many wild plants have some level of activity) and seek out more powerful ones occasionally and for specific situations.

This week as I tried to lower my coffee usage or stop altogether, I had dropped from 3 cups a day to 1. That one suddenly started to make me feel noticeably high, like a bump of cocaine in the morning. I realised that I craved it in the same way and it clicked for me - coffee is literally just a drug I like to take by myself and read the newspaper. It's no different. It's the first thing I think of in the morning because I'm addicted. Currently trying to go cold turkey.

Caffeine evolved to deter insects. Coffee, tea, chocolate and some other plants all evolved caffeine independently due to similar evolutionary pressure.

> But maybe that's why I started drinking coffee?

you don't remember why, do you?

There's a decent amount of research going into the hormones that our GI biome produce and how it affects us. Our body has a few different biomes and they all seem to play somewhat important roles.

Yeah there's nontrivial evidence that among other things, the complex community living inside you manipulates your brain.

The paper is about previously unknown ways coffee affects the body.

I was so surprised at this headline that I nearly leapt out of my chair!

Humans known since 45 minutes after first drink

I find that the effects can be pretty subtle, and if I'm already tired there's usually no coming back. What I think has worked best for me is to re-up on caffeine a few hours before I think I'll be tired, or around when a previous dose is wearing off. Also, if trying to stay awake, food and entertainment are also quite important. If I hit a point where I'm hungry, cold, and tired, and going to the kitchen to eat sounds like a chore, it's usually too late for me. When the bed's closer, it's hard to resist.

I've also noticed that I have a sort of natural energy in the morning. I think of it as being similar to how a seed has enough energy in itself to sprout and then get sunlight. It's probably so I can make myself eat and whatnot. I don't really need caffeine to "wake up" as much as I need it to stay awake later in the day, and even if I do have a coffee with breakfast, I'll often get tired before the normal day is over.

I think this description is often associated with ADHD memes.

Falling asleep after a can of energy drink.

tea also has caffeine, although in smaller quantities. Maybe you mean that you don't care so you go by taste, just specifying because there's a common misconception about tea not having caffeine.

If the effect size is big small sample sizes does not matter as much as otherwise.

You really have to look at the power analysis and the sample size together.

Saying this as a general truth. I am not sure about the power of the method in this papper, i only read the abstract.

Studies seem to indicate that coffee is at least as healthy, if not healthier than tea, and I have not heard this about caffeine specifically (aka the same effects coming from pills or energy drinks).

One fun fact: we still haven’t figured out why coffee makes us poop. We’ve studied every chemical in there and can’t seem to find a link, but the association is uh… well-known.

There have been positive and negative reports for a long long time. If coffee was going to kill us, I’d certainly have died in school!

Don't fret. You're allowed to enjoy things that aren't part of the scientific reductionist longevity influencer lifestyle fad :)

Maybe I have some neurological issue or something but whenever I quit coffee I find it extremely difficult to maintain any kind of motivation to sit in an open plan office and code. Coffee makes me a worker bee, I can understand why employers give it away for free.

So, the coffee stays for now.

Coffee in general is unreasonably healthy as a beverage. The overwhelming majority of science agrees it’s a quality health drink.

Relax. Tomorrow there will be a paper/article saying coffee is great for you.

Did you know:

    By replacing your morning coffee with herbal tea, you can remove up to 87% of the little joy you still have left in your life.  /s

Keep the coffee buddy.

Could you elaborate on how to interpret your comment without it leading to anti-intellectualism?

You are missing the point.

If you can predict someone's coffee intake based on testing of their microbiome then you've proven that coffee intake has predictable effects on the microbiome.

The important part isn't predicting coffee use, it's just the proof that there's you can predict and perhaps control in the opposite direction leading to more research.