Another thing to remember though is with body heat, it raises with metabolism for one. A big thing though is losing weight and improving lean mass means better circulation. Many times people with poor circulation have freezing cold extremities because the body can't heat them as well.

For some reason the quote up there makes me think they are saying we should have a high carb diet because more calories would be burned as heat and we'd lose weight more. Maybe I'm misreading it though.