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17 September 2014
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Caffeine and the Brain


Does caffeine give us a mental edge?

Caffeine is the most widely used psycho-stimulant substance in the world. As office hours get longer so does our coffee consumption with global consumption estimated at over 120,000 tons per annum.

But does caffeine really have any benefits on our mental performance? The wide array of available information on the subject can be confusing so we tried to test it out for ourselves.

"decaf had reduced blood pressure, reduced anxiety and improved sleep"

Enter DJ David Sheppard and roving reporter Maggie Philbin, two self-confessed coffee addicts who rely on their liquid fixes to get them through their gruelling 5am starts. We put one of them through cold turkey for a week to see what happens to brain function when caffeine is removed.

By testing their concentration, reaction times, hand steadiness, blood pressure and mood at various points over seven days we were able to compare this data to the data taken when we gave them back their poison at the end of the week. Neither of them knew who had been given the decaf substitute.

It is thought coffee users perform better after they have imbibed a cup of coffee. But is this due to a net benefit of caffeine or might it be that coffee addicts have an impaired mental performance before drinking coffee because they are in a state of withdrawal?

By the end of the week David, who was on the decaf, had reduced blood pressure, reduced anxiety and improved sleep. The caffeine withdrawal affected his alertness, hand steadiness and reaction time, plummeting on day two and slowly restoring itself by days six and seven. His performance at the end of the trial, after a full withdrawal, was as good as it was before which shows the caffeine only had an effect insomuch as his body was craving it.

David was so affected by his withdrawal that there were even murmurings of the team switching to decaf as a permanent measure.

Does caffeine give us the edge over decaf users? No. Once we've recovered from caffeine we can do just as well without it.

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