
Study: Coffee unrelated to alertness, Stimulating effects may be illusion - alexandros
http://www.sciencedaily.com/releases/2010/06/100602211940.htm
======
goodside
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.

~~~
frankus
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.

But that's probably just the drug talking.

------
tumult
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.

~~~
robfitz
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.

~~~
khafra
I drink coffee because it's correlated with a 70% lower chance of cirrhosis of
the liver, and I'm pretty sure liquor doesn't have a placebo effect.

------
lionhearted
If you drink caffeine, you should probably spend an hour or two at some point
learning the basics of how it works.

<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.

~~~
sliverstorm
this is interesting. caffine never does a damn thing to me, which leaves me
wondering what part of the chain is broken & why...

I wonder if there's any tests i can do to learn more about myself in this
regard.

~~~
sounddust
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).

* <http://en.wikipedia.org/wiki/CYP1A2>

------
tmsh
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..

~~~
seabee
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'."

~~~
tmsh
I see now, thanks. So:

    
    
      For medium/high caffeine consumers:
       placebo -> decrease (and headache)
       caffeine -> 'level 1'
      Non/low caffeine consumers: 
       placebo-> 'level 1' 
       caffeine -> 'level 2'
    

(where level 2 > level 1).

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.

------
jrockway
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.

------
cammil
I'd just like to point out that illusions are often as good as the real thing.

If your brain believes you are more alert, chances are, to all intents and
purposes, you will be more alert.

~~~
billswift
You mean like the way drinkers think alcohol makes them wittier and more
charming?

------
ronnoch
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.

~~~
dlib
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.

------
d3vvnull
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.

~~~
billswift
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...](http://williambswift.blogspot.com/2010/01/drugs-and-their-non-
effects.html)

------
T_S_
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.

Whew! Time for a second cup.

------
xsive
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.

------
marknutter
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.

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confuzatron
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 :-/

~~~
ecuzzillo
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.

------
olsonea
Baloney.

------
jarin
My world has just been destroyed.

