Yeah, there's a huge psychological component to these things. I have a family member who has always been a bigger person (not 900 lbs big, but very overweight) his whole life. He insists that "I just can't lose weight, it's just not possible for me." He goes on diets for a week or two, and if he doesn't see huge losses, he gives up. Or, he says "I went for a walk 3 times last week and I didn't lose a frickin' pound." Meanwhile, he's eating out for just about every meal and that includes McDonald's at least once a week.
I'm grateful to not have any addictive tendencies. I'm also glad I learned about nutrition during and after college. My family did not have any understanding of nutrition growing up. I would easily down a 12 pk of Mt. Dew on the average Saturday when I was in grade school and HS. I'd play a baseball game and then down a quart of ice cream. I was young and my body could absorb those things without being overweight, but I still wasted a lot of prime physical years by participating in horrible nutrition.
