I could've sworn I saw the 20% figure bandied about before. What is more interesting is the % increase in that figure based on mental exertion. I'm being hopel

I could've sworn I saw the 20% figure bandied about before. What is more interesting is the % increase in that figure based on mental exertion. I'm being hopeless now with unreferenced hearsay, but I'm sure I read (perhaps in New Scientist?) that the actual caloric increase is minimal, but measurable.