What about non-addicts? I very rarely drink caffeine (just midterms and finals, basically) but I'm pretty sure that when I do, the effects are no illusion.
Same here, in fact I try to keep my tolerance of caffeine at such a level that whenever I have to pull through I can get by with coffee. It really helps and don't think it's a placebo.
The headline is a little misleading. For regular and heavy coffee drinkers, the study suggests that a cup of coffee merely brings the person out of caffeine withdrawal, and does not provide any stimulation. Since caffeine withdrawal makes you groggy and less alert, it means that regular caffeine drinkers have to consume caffeine just to reach the level they would have already been at if they weren't consuming caffeine regularly.
For people who don't currently have a tolerance for caffeine, it most certainly does provide stimulating effects.
It also seems like the study gave participants the equivalent of a single cup of coffee. If you need more than that for your buzz, looks like you'd have been out of luck.
> For people who don't currently have a tolerance for caffeine, it most certainly does provide stimulating effects.
Oh yes! I rarely drink much caffeine. I once went for a bike ride where I was rapidly wearing out towards the end, and some guy gave me a sugar/caffeine packet. I went off like a rocket after that...
This line of reasoning often leads to the suggestion that you shouldn't bother drinking coffee. I think it's exactly the opposite.. Most things that give me as much pleasure as coffee does are actively damaging me. If coffee is a break-even prospect, then it may just be the world's greatest vice.
This is also true of nicotine. Smokers say that a cigarette 'calms the nerves', but if you measure their anxiety levels you find that it only relieves the withdrawal symptoms and returns them to the normal range.
For some weeks after I stopped drinking coffe each time I had a cup of, say, barley coffee (which is caffeine free) I would get a buzz. It's an interesting experiment that demonstrated, to me, the strength of the placebo effect.
I am no coffee drinker, but I'm surprised that they think their results are conclusive based on a single instance of a placebo administered. Especially when the results are so neurological, that surely the brain compensates the first time a placebo is given -- and gradually (like with any neurotransmitter-affecting chemical) gets rid of its self-generating effects.
'Tests on 379 individuals who abstained from caffeine for 16 hours before being given either caffeine or a placebo...'
Seems like -- cue Pavlovian response, but in your brain.... I'd be more impressed if they were given the placebo/caffeine for a week and still performed the same on the tests..
Read the article more closely, no Pavlovian response occurred:
"The medium/high caffeine consumers who received the placebo reported a decrease in alertness and an increase in headache, neither of which were reported by those who received caffeine. However, their post-caffeine levels of alertness were no higher than the non/low consumers who received a placebo, suggesting caffeine only brings coffee drinkers back up to 'normal'."
However, I still think there might be some confusion in using a single instance for testing, esp. testing alertness. There might be a large withdrawal symptom going on in the brain that first time that makes alertness more difficult in general.
I am a heavy coffee drinker; I like the taste and thought I was getting some stimulant effect. But last fall and early winter I tested myself (described a little more here - http://williambswift.blogspot.com/2010/01/drugs-and-their-no...) varying my dosage of caffeine, but keeping it steady at each dosage for a week at a time. And discovered I could find no evidence of any effect at all on me.
Long story really short - you've got this hormone called adenosine that tells you when you're tired. Andenosine floats around and attaches itself in your brain to an andenosine receptor. As it attaches, you feel tired.
Caffeine is shaped similarly to andenosine, so it sort of "blocks" the andenosine from getting to the receptor. You're still tired, you still need rest, but you don't feel tired. So that's the tiredness-removal effect of caffeine, it's stopping the andenosine from getting to the receptor.
Now, your body kind of minorly panics at this and secretes adrenalin - y'know, adrenalin, like when you get excited or sacred? Yeah, that one. When andenosine gets cut off, your body perks up like something is happening and releases adrenalin. So there's the energy boost.
Over time, your body start naturally producing more andenosine to compensate, hence, you need caffeine just to feel normal. And your body starts to realize that you don't need the adrenalin, so you start to produce less of it when having caffeine. If you've ever gone a while without caffeine and then had a coffee, you remember how off the wall hyper you got? That slowly fades because your body starts producing more andenosine (the sleepy hormone) if you're a habitual caffeine user, and less adrenalin.
There's more to it than that, but that's some of the basics. Wikipedia's got some decent stuff, a few minutes here and there skimming on this sort of thing is time well spent.
Some people have a gene that causes them to metabolize caffeine much more quickly than others. I found this out by taking the 23andMe DNA test and discovering that I have this gene, which makes sense as it seems that I'm less affected by caffeine than others (although I make up for it by drinking more).
I'm at the point of maybe three or four cups a day. But really, coffee doesn't even keep me awake anymore, if anything it's the exact opposite in that I can be alert (not fully awake, but aware), and the second I grab a cup of coffee I start feeling drowsy after it's gone.
Incidentally, I am the opposite. When I wake up in the morning, I feel awake and alert. Then I have coffee, and I feel amazing. If I have coffee after I get home from work, I can't go to bed before 5am, regardless of when I got up the day before.
I consume a fair amount of caffeine every day, and I still have a buffer where I can use more to get more effect, or use less and not feel bad. FWIW, though, I also sleep a lot, especially on the weekends. I think the harm comes from chronically not sleeping, not delaying sleep by a few hours once in a while.
Or, I've damaged my brain and I can't recognize adverse effects anymore. That's the great thing about brain damage, if you do it right, your brain is too damaged to realize that your brain is damaged. Life is just an illusion! ;)
Great explanation. When I was drinking 10+ cups of coffee/day, I was not only not feeling perked up (pun indented) but more tired. I guess I was producing way too much andenosine.
This is a depressing article. I like drinking coffee, and now it turns out that it's making me groggy and un-alert by default.
I think I've noticed this at weekends - I drink lots of coffee at work all week, and then at the weekend I'll maybe desist for a day, and end up not doing anything productive. Then when I have a cup, I am suddenly infused with get up and go. I really need to cut down :-/
I'm thoroughly addicted to coffee by now, and I'm not sure it's so bad, as long as the experience of buying-making-drinking the coffee is a good one, involving fresh beans, happy, independent coffee purveyors, zen coffee-making, and good-tasting coffee.
It may also be that it's not just the coffee for some of us. I have a whole ritual early in the morning around making my coffee. I grind the beans, put on the water to boil. And I brew the coffee in my French press. After I've had a couple of cups of coffee at the beginning of the day, I feel really good and ready to start my day. The expectation and enjoyment of that cup of coffee should be factored in.
That is one reason why, when I tested my response to caffeine last fall and early winter, I used decaf coffee, regular coffee, and coffee with added caffeine (pills) to test for an effect. http://williambswift.blogspot.com/2010/01/drugs-and-their-no...
The results are interesting, but there's a methodological limitation the article isn't emphasizing as strongly as it should.
An illustrative analogy: Suppose you organize a group of people who often take painkillers for headaches, and a group that takes painkillers only rarely. You find that headaches of the regular painkiller-takers are no better with their painkillers than the non-painkiller-takers are without painkillers. Can you conclude from this that painkillers have no long-term effects on headaches? You can't, because the reason the first group was taking pain killers in the first place was probably because they have bad headaches, while the second group doesn't. The painkillers just bring them into parity.
The problem is the two groups the coffee study compares were not assigned their subjects randomly. They're made up of people who choose freely to drink or not drink coffee. The fact that regular coffee drinkers are no better with coffee than non-drinkers are without coffee doesn't necessarily mean that coffee has no long-term effect. It could well be that non-drinkers already have endogenously whatever benefits caffeine provides, and drinkers do not, and coffee brings them up to parity.
In other words, the current study has nothing to say on what happens to people when their long-term coffee drinking habits are changed from what they would normally prefer them to be, and so you can't infer much about the benefits or drawbacks of such changes. You could control for this by assigning people randomly two two groups, have one group drink coffee regularly for a few months while the other abstains, and then repeat the experiment performed here. The results of this modified experiment would determine whether current ad-lib drinkers should stop drinking coffee and whether current non-drinkers should start.
That's exactly what I was going to say. It could be that high caffeine users are biologically predisposed to need frequent doses of a stimulant to maintain a level of alertness that is merely normal for the general population, like some kind of ADHD spectrum disorder.
So basically, being a coffee drinker I control when I feel alert and when I feel groggy. Sounds good to me. Before I was a heavy coffee drinker I was at the whim of my body's rhythms.
This article mentions nothing about how they measure alertness. How objectively can this possibly be measured?
It seems to me that the measure of alertness may only be indirectly measured in by task specific performance. So there may be driving alertness, data-entry alertness etc...
On the other hand, even if all the chemical effects are quantifiable, so the measure is "objective", does that really mean anything for different individuals?
Also, for a given task, it may turn out that I need the anxiety producing effects of caffeine just to care enough to perform the drudgery.
I can sort of see this; if I've already had caffeine, any warm beverage seems to continue the resulting productivity flow. It's nice at night because I can be awake as long as I want to be, but then be able to sleep when I come down from the flow state.
Incidentally, yesterday I decided to take a 200mg caffeine pill. After that, I saw several new colors that I have never seen before. And I solved some problems that had been bugging me for a few weeks, and implemented them, and watched TV, and read a book. And slept well.
Caffeine may be bad for spiders building webs, but I'm not convinced that it's useless (or bad) for humans.
36 comments
[ 3.9 ms ] story [ 80.8 ms ] threadFor people who don't currently have a tolerance for caffeine, it most certainly does provide stimulating effects.
It also seems like the study gave participants the equivalent of a single cup of coffee. If you need more than that for your buzz, looks like you'd have been out of luck.
Oh yes! I rarely drink much caffeine. I once went for a bike ride where I was rapidly wearing out towards the end, and some guy gave me a sugar/caffeine packet. I went off like a rocket after that...
By the time I'm actually done making coffee, somehow, I end up not so tired and end up barely needing to finish my first cup.
If your brain believes you are more alert, chances are, to all intents and purposes, you will be more alert.
'Tests on 379 individuals who abstained from caffeine for 16 hours before being given either caffeine or a placebo...'
Seems like -- cue Pavlovian response, but in your brain.... I'd be more impressed if they were given the placebo/caffeine for a week and still performed the same on the tests..
"The medium/high caffeine consumers who received the placebo reported a decrease in alertness and an increase in headache, neither of which were reported by those who received caffeine. However, their post-caffeine levels of alertness were no higher than the non/low consumers who received a placebo, suggesting caffeine only brings coffee drinkers back up to 'normal'."
However, I still think there might be some confusion in using a single instance for testing, esp. testing alertness. There might be a large withdrawal symptom going on in the brain that first time that makes alertness more difficult in general.
http://en.wikipedia.org/wiki/Caffeine#Mechanism_of_action
Long story really short - you've got this hormone called adenosine that tells you when you're tired. Andenosine floats around and attaches itself in your brain to an andenosine receptor. As it attaches, you feel tired.
Caffeine is shaped similarly to andenosine, so it sort of "blocks" the andenosine from getting to the receptor. You're still tired, you still need rest, but you don't feel tired. So that's the tiredness-removal effect of caffeine, it's stopping the andenosine from getting to the receptor.
Now, your body kind of minorly panics at this and secretes adrenalin - y'know, adrenalin, like when you get excited or sacred? Yeah, that one. When andenosine gets cut off, your body perks up like something is happening and releases adrenalin. So there's the energy boost.
Over time, your body start naturally producing more andenosine to compensate, hence, you need caffeine just to feel normal. And your body starts to realize that you don't need the adrenalin, so you start to produce less of it when having caffeine. If you've ever gone a while without caffeine and then had a coffee, you remember how off the wall hyper you got? That slowly fades because your body starts producing more andenosine (the sleepy hormone) if you're a habitual caffeine user, and less adrenalin.
There's more to it than that, but that's some of the basics. Wikipedia's got some decent stuff, a few minutes here and there skimming on this sort of thing is time well spent.
I wonder if there's any tests i can do to learn more about myself in this regard.
* http://en.wikipedia.org/wiki/CYP1A2
I'm at the point of maybe three or four cups a day. But really, coffee doesn't even keep me awake anymore, if anything it's the exact opposite in that I can be alert (not fully awake, but aware), and the second I grab a cup of coffee I start feeling drowsy after it's gone.
I consume a fair amount of caffeine every day, and I still have a buffer where I can use more to get more effect, or use less and not feel bad. FWIW, though, I also sleep a lot, especially on the weekends. I think the harm comes from chronically not sleeping, not delaying sleep by a few hours once in a while.
Or, I've damaged my brain and I can't recognize adverse effects anymore. That's the great thing about brain damage, if you do it right, your brain is too damaged to realize that your brain is damaged. Life is just an illusion! ;)
I think I've noticed this at weekends - I drink lots of coffee at work all week, and then at the weekend I'll maybe desist for a day, and end up not doing anything productive. Then when I have a cup, I am suddenly infused with get up and go. I really need to cut down :-/
An illustrative analogy: Suppose you organize a group of people who often take painkillers for headaches, and a group that takes painkillers only rarely. You find that headaches of the regular painkiller-takers are no better with their painkillers than the non-painkiller-takers are without painkillers. Can you conclude from this that painkillers have no long-term effects on headaches? You can't, because the reason the first group was taking pain killers in the first place was probably because they have bad headaches, while the second group doesn't. The painkillers just bring them into parity.
The problem is the two groups the coffee study compares were not assigned their subjects randomly. They're made up of people who choose freely to drink or not drink coffee. The fact that regular coffee drinkers are no better with coffee than non-drinkers are without coffee doesn't necessarily mean that coffee has no long-term effect. It could well be that non-drinkers already have endogenously whatever benefits caffeine provides, and drinkers do not, and coffee brings them up to parity.
In other words, the current study has nothing to say on what happens to people when their long-term coffee drinking habits are changed from what they would normally prefer them to be, and so you can't infer much about the benefits or drawbacks of such changes. You could control for this by assigning people randomly two two groups, have one group drink coffee regularly for a few months while the other abstains, and then repeat the experiment performed here. The results of this modified experiment would determine whether current ad-lib drinkers should stop drinking coffee and whether current non-drinkers should start.
But that's probably just the drug talking.
It seems to me that the measure of alertness may only be indirectly measured in by task specific performance. So there may be driving alertness, data-entry alertness etc...
On the other hand, even if all the chemical effects are quantifiable, so the measure is "objective", does that really mean anything for different individuals?
Also, for a given task, it may turn out that I need the anxiety producing effects of caffeine just to care enough to perform the drudgery.
Whew! Time for a second cup.
Incidentally, yesterday I decided to take a 200mg caffeine pill. After that, I saw several new colors that I have never seen before. And I solved some problems that had been bugging me for a few weeks, and implemented them, and watched TV, and read a book. And slept well.
Caffeine may be bad for spiders building webs, but I'm not convinced that it's useless (or bad) for humans.