What sounds like an urban myth has been proven by researchers at the University of Northumbria...
Research conducted at the University of Northumbria in Newcastle, England has linked our ability to remember chunks of information to chewing gum. 75 participants in the study were asked to take part in a 20-minute memory test in which:
One third of participants chewed gum
One third carried out the motions of chewing gum, without any actual gum
A one-third control group did not chew gum
Researchers found that recall was improved by 35% among participants who chewed gum, most significantly in delayed word recall tests; perhaps indicating possible benefits for students revising for, and taking exams, chewing gum.
In a more recent experiment, Edward McLaughlin (2007) repeated the study with Wrigley's 5 gum at Cornell University and found similar improvements in recall and concentration among participants.