I wish full meant something to me. I'll eat until I burst, as long as it tastes good.

Anyway, you can measure portions with your fist. Never eat a portion of anything that is any larger than your fist. Now, this doesn't mean you can have a fist-size serving of potatos and a fist-size serving of pasta and a fist-size serving of chocolate cake. But of the things you are supposed to eat, a fist is enough.