I am not an endurance athlete, and I wouldn't even consider myself a health nut, but I know that i wake up hungry, and if I don't eat something (usually a fruit and greens smoothie with protein power and almond milk), I get too hungry to focus on work. I've also noticed that since I got more rigorous about eating (drinking) breakfast, I don't get as hungry late at night. It's almost, anecdotally, like my body know it can expect fuel in the morning and doesn't spend the evening stockpiling.