As someone who was previously obese, I tend to believe that there is a good argument for genetic variation being a cause of weight gain. I'm sure that some peo

As someone who was previously obese, I tend to believe that there is a good argument for genetic variation being a cause of weight gain. I'm sure that some people gain weight easily even on small amounts of food, but I think variation in food desire is a much larger part of the problem. While I have lost all of my excess weight, it's been a challenge keeping it off. I really love to eat, and I sometimes fixate on the thought of eating some chocolate/cake/whatever to the extent that it becomes hard to concentrate. If I do give in and have some I need to eat a whole load before I'm satisfied - and I've been this way ever since I was a little kid. My wife, on the other hand, experiences much rarer cravings and is satisfied even with a small amount of the food in question. I wonder if the weight gain in the US can be partly explained by higher availability of extremely fattening foods combined with greater societal acceptance of obesity - has the commonly accepted portion size gone up, for example? This makes it easier for those with greater food desire to satisfy their urges. edit: removed extraneous word