Last reviewed 8 October 2019

College students who averaged six and a half hours of sleep a night were found to achieve grades that were 50% lower than other students who averaged just one hour more of sleep.

The above are the recent findings of research from the Massachusetts Institute of Technology (MIT) which concluded a strong relationship between students’ grades and how much sleep they were getting.

The experiment involved 100 students in an MIT engineering class who were given Fitbits, the popular wrist-worn devices that track a person’s activity 24/7, in exchange for the researchers’ access to a semester’s worth of their activity data.

The findings — some unsurprising, but some quite unexpected — have been reported in the journal Science of Learning.

The study found that the time students go to bed and the consistency of their sleep habits make a big difference.

Interestingly, getting a good night’s sleep just before a big test is not good enough — it takes several nights in a row of good sleep to make a difference.

Another surprise from the study was that individuals who went to bed very late, for example 2am, tended to perform less well on their tests no matter how much total sleep they ended up getting.

Commenting on the research, Professor Robert Stickgold, a Director of the Center for Sleep and Cognition at Harvard Medical School, who was not connected with the study, said, “The results of this study are very gratifying to me as a sleep researcher, but are terrifying to me as a parent.

“The overall course grades for students averaging six and a half hours of sleep were down 50% from other students who averaged just one hour more sleep. Similarly, those who had just a half-hour more night-to-night variation in their total sleep time had grades that dropped 45% below others with less variation. This is huge!”