A coffee break really does keep you going at work. Researchers from the London School of Hygiene and Tropical Medicine reviewed 13 separate studies from around the world involving shift workers in simulated working conditions. Participants in the studies were given tests of their memory, concentration, use of words and reasoning and also of how prone they were to making simple errors. Some were given a placebo while others were given caffeine. Whatever form the caffeine was given in - a cup of coffee, an energy drink or a pill - those who had been given the caffeine scored moderately better than those given a placebo. Taking caffeine had a similar effect to taking a "power nap."
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