NEW requires thinking, and thinking burns up glycogen and such things (the brain can burn 20-40% of calories sometimes I think, depends), so yeah, it will, but I'm not sure if it would be less or more than any regular thinking, which varies a lot anyway. Beyond that...

I'm not sure. Creating energy requires it, yes, but RB's description implies that while you can get energy from food, it doesn't sound like the kind you burn if you can also get it from breathing and grounding and all that. Some kind of 'life energy' I think, which may be related to the sunlight and water and soil all food comes from.