Coffee consumption unrelated to alertness

June 2, 2010, University of Bristol
Coffee consumption unrelated to alertness

(PhysOrg.com) -- The stimulatory effects of caffeine may be nothing more than an illusion according to new research, which shows there is no real benefit to be gained from the habitual morning cup of coffee.

Tests on 379 individuals who abstained from caffeine for 16 hours before being given either caffeine or a and then tested for a range of responses showed little variance in levels of alertness.

The study, published online in the journal of Neuropsychopharmacology, reports that frequent coffee drinkers develop a tolerance to both the anxiety-producing effects and the stimulatory effects of caffeine. While frequent consumers may feel alerted by coffee, evidence suggests that this is actually merely the reversal of the fatiguing effects of acute . And given the increased propensity to and raised induced by , there is no net benefit to be gained.

Peter Rogers, from the University of Bristol’s Department of Experimental Psychology and one of the lead authors of the study, said: “Our study shows that we don't gain an advantage from consuming caffeine - although we feel alerted by it, this is caffeine just bringing us back to normal. On the other hand, while caffeine can increase anxiety, tolerance means that for most caffeine consumers this effect is negligible.”

Approximately half of the participants were non/low caffeine consumers and the other half were medium/high caffeine consumers. All were asked to rate their personal levels of anxiety, alertness and headache before and after being given either the caffeine or the placebo. They were also asked to carry out a series of computer tasks to test for their levels of memory, attentiveness and vigilance.

The medium/high caffeine consumers who received the placebo reported a decrease in alertness and an increase in , 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'.

The authors also found that the genetic predisposition to anxiety did not deter coffee drinking. In fact, people with the gene variant associated with anxiety tended to consume slightly larger amounts of coffee than those without the variant, suggesting that a mild increase in anxiety may be a part of the pleasant buzz caused by .

More information: The paper; Association of the Anxiogenic and Alerting Effects of Caffeine with ADORA2A and ADORA1 Polymorphisms and Habitual Level of Caffeine Consumption; is published online in the journal of Neuropsychopharmacology. www.nature.com/npp/index.html

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6 comments

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Rooster
not rated yet Jun 02, 2010
Yeah but...what about those who have that nagging effect of the neurological disorder called "ADHD"?
My doctor says..."Of course you need to have an intake of coffee at various points during any given day...it's harmless, much more so than the drugs which one can REALLY become dependent upon...and for people with ADHD such as you have...is understandable as a replecement for those drugs."
Please, don't forget to take everyone into account before you have a knee-jerk reaction towards the relative 379 few. Smoking a little dope every now-and-then doesn't hurt either. Btw, I'm 60 years old...and have developed a fairly good sense of what helps and what doesn't.
magpies
not rated yet Jun 03, 2010
Ya and going sky diving also has no effect...
TheMuskyBuck
1 / 5 (1) Jun 03, 2010
I can't help but leave a comment on this paper.

I try not to blog or leave comment but in this case...well when you read bunk and you know it's trading on obvious whilst bunking you just have to say something.

A time ago, I used to be a morning radio host.

When I first took that job, I didn't drink coffee. The first three months of doing morning radio was absolute hell. As well as my hair falling out, constant heartburn for three months (popping Zantac daily), my mouth wouldn't engage properly.

There wasn't anything technically wrong. But from 5:30 am when I first signed on until around 8am there was constant problems as if my thoughts were hitting my mouth like a car hitting a speed bump at 50km per hour.

So I decided to start the morning with a large cup of coffee from my local Tim Hortons location.

And the difference was profound. I'd ask the researchers, how my advantages found in drinking coffee can be boiled down to withdrawl.
antialias_physorg
1 / 5 (1) Jun 03, 2010
I think you didn't read the paper. Like any drug coffeine can stimulate _if you are not used to it_. But after you have acclimatized yourself to the drug you're back to square one.

Actually worse, since you now have to keep on using the drug in order to function even at your previously 'unaugmented' level.
otto1923
not rated yet Jun 03, 2010
Like any drug coffeine can stimulate _if you are not used to it_.
Not necessarily... nicotine has absolutely no net effect at all, other than to relieve its own pernicious withdrawal symptoms. Add caffeine to the list of worthless addictive drugs- including antidepressants. At least coffee and tea contain some antioxidents. And no, I wont stop drinking Monster- maybe its the taurine.
damnfuct
not rated yet Jun 10, 2010
Can this be considered new? Once dependency has been formed, users typically have to take more of most any drug in order to feel the same effects. It's not like this is some big mystery.

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