Haha really man? I'm little too, but I can down an entire pizza
You could just say that you are "eating healthy" instead of "on a diet" or something like that. I am really skinny too and whenever I avoid bad foods I just tell my friends that I'm trying to be healthy and that pizza is really bad for you. I just say it in a way that doesn't imply that I would want to lose weight.
And how did you eat an entire large pizza lol? I can only eat 5 slices at the most.
Yeah I've always been able to eat a whole pizza by myself - think there must be something out with our metabolism