Chewing a gum five minutes before you take a test could be all that it takes to boost your performance
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They found that chewing gum five minutes before starting the test provided a mental boost for the first 20 minutes of the test. However chewing gum during the test proved to be counterproductive and distracted the brain from mental or thinking processes.
“Clear performance advantages emerge when gum is chewed prior to (but not during) [mental] testing”, the researchers wrote in their report which has been published in the journal Appetite.
Source-Medindia