"...and he's struggling with hunger and trying to lose more weight." This is all I was really trying to emphasize. When it comes time to burn energy, calories

"...and he's struggling with hunger and trying to lose more weight." This is all I was really trying to emphasize. When it comes time to burn energy, calories are the same, but this isn't true when eating. High sugar affects insulin and other things that may it hard for people to stick with it. Eating meals high in fat provides higher satiety (you feel full longer). Eating vegetables high in fiber fills your stomach with large mass but low sugar so you'll feel full longer while that breaks down.