I tend to lose weight when I am into a game.
I come home from work at 5PM, and fire the game up for a quick quest before dinner. Well, that leads to another quest, and then I look at the clock and it is 11 PM and I still have not ate. So, I play some more and go to bed without my dinner. Games have become my disciplinarian parent.

I use games in much the same way to lose weight.

Games require both hands, you can't use one to stuff your face at the same time so even snacking is not possible.