I'll often work out in the morning without eating. I read somewhere that this helps burn fat. I don't know if that's true. What I DO know is that I'm very hungry after the fact. Very.
In fact, I'm so hungry that I will often start singing that little song from the Oliver Twist movie where the little orphan kids are begging for gruel and stuff.
My dog does this all the time though. Whenever I start digging into his food bag he starts going all crazy and slobbering and stuff. Food glorious FOOD! I see it in his eyes.