actually id be inclined to think adults are better at portion control than kids. if a child knows when they are full and is going to stop eating you dont get 300 pound 8 year olds. but like i said, it all goes back to the history of our species. we will eat as much as we have access to because thousands of years ago that might have been all you got for a while. and thats a problem with restaurants these days. the portions are massive but we eat it all, even though its too much food. especially 'all you can eat' or buffet style places. you always come out thinking 'i ate too much'. basically, there are a lot of things that need fixing if we are going to get rid of this problem.