Researchers recorded the behavior of 447 undergraduate students across three different cohorts in relation to whether students brought drinks, and the type of drinks they brought, into exams. Students who were in higher levels of the university degree were much more likely to bring drinks into the exam that those in their first year of undergraduate study.
The researchers related the marks attained by students in the exam to whether those students brought water into the exam. Importantly, they controlled for general ability using coursework marks to ensure that they were not simply assessing the possibility that more able students were more likely to bring water into the exam. The results showed that those who took water into the exam, and presumably consumed the water, did better in the exam than those who did not.
Dr Pawson said: "The results imply that the simple act of bringing water into an exam was linked to an improvement in students' grades. There are several physiological and psychological reasons that might explain this improvement with water consumption."
Dr Pawson raised the possibility that water consumption may have a physiological effect on thinking functions that result in improved exam performance.. He also proposed the possibility that consuming water may alleviate anxiety, which is known to have a negative effect on exam performance.
Dr Pawson said: "Future research is needed to tease apart these explanations, but whatever the explanation it is clear that students should endeavour to stay hydrated with water during exams."
These findings could have implications on policy for access to drinks during examinations at all levels of education. They also suggest that information about the importance of keeping hydrated should be targeted at first-year undergraduate students who are less likely to bring drinks into exams.