A cup of coffee in the morning is no more effective than a placebo at sharpening up people's thought processes. Researchers from the University of Bristol studied 379 people who were deprived of caffeine for 16 hours before being given either caffeine or a placebo. The participants then took a series of tests to measure their attentiveness, memory and vigilance. The study found "little difference" in the results between the coffee users and those who were given placebos. In cases where the caffeine did make an improvement this was actually a case of bringing caffeine users performance back up to the levels of non caffeine users.
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