asked students to engage in three different activities. First they simply sat and relaxed. Then they completed a series of memory and attention tests. Finally, they were told to read and summarize a text. After forty five minutes performing each of these tasks, the students were offered an all-you-can eat buffet.

The actual caloric expenditure of performing any of these tasks was minimal. Intellectual work burns only three more calories an hour than merely sitting and relaxing. But when these students used their noggins (Activities 2 and 3) they later consumed 200 - 250 more calories than the students who had merely sat and relaxed.

Blood samples drawn before, during, and after the activities offer a possible explanation. Intellectual activities cause wide fluctuations in glucose and insulin levels, and may trigger hunger — resulting in the students eating far more than they actually expended in the activity. The researchers called it “caloric overcompensation” — in other words, after using their brains, they ate too much. They concluded that jobs involving intellectual tasks, combined with the sedentary nature of that work, could contribute to our society’s currently problem with obesity.

Read her entire post here.