"I'm not obese because I've been over eating. I've always over eaten" The printing isn't new and neither are the recessions. They're just making them worse.
If you've been eating the same for the last 20 years and you've been gradually gaining weight over the last 20 years, then it's your diet.
If you've been eating the same for the last 20 years and you suddenly gain weight, it's likely not your diet, it's something else -- exercise, illness, et cetera.