"My girlfriend and I used to leave highschool at lunch and eat a 'burger' or a bag of chips and a coke and I had a 22inch waistline."
Everybody metabolizes differently. Some people can eat anything they want and get away with it, while others, struggle with each bite. Some just pass a burger stand and get a smell, and put weight on. However, as we get older, moderation and exercise of any kind will do wonders. For sure, among other things, out of control sugar eating will eventually do a number on the best of us, and do you in.
Yes, I know that's right. My Mother in law is the biggest 'sweets' eater and doesn't gain weight.