Here’s a reason to rest your brain. Too much thinking could cause you to pack on the pounds.

Researchers from the University Laval in Quebec, Canada, found that the stress of thinking caused “heavy” thinkers to eat more calories, the U.K.’s Daily Telegraph reported Wednesday.

The research team measured the food intake of 14 students following three different tasks, which included relaxing in a sitting position, reading and summarizing a text, and finally, completing a series of memory, attention, and vigilance tests on the computer, according to the report.

After 45 minutes at each activity, students were invited to eat as much as they wanted from a buffet.

And despite the low energy cost of intellectual work, students spontaneously consumed 203 more calories after summarizing a text, and 253 more calories after the computer tests than they did after relaxing in the sitting position, the Telegraph reported.

Blood samples taken before, during, and after each session revealed that intellectual work causes much bigger fluctuations in glucose and insulin levels than rest periods.

"These fluctuations may be caused by the stress of intellectual work, or also reflect a biological adaptation during glucose combustion,” said Jean-Philippe Chaput, the study's main author.

Click here to read more from the Daily Telegraph.