We spent many happy summers when kids were young, travelling through France. Even then, 20 years ago, there were many overweight French people. Nor morbidly obese: but my observation was that as they get older (40+?) French people put on weight, going up several sizes in clothes. Many men and women in the towns, supermarkets and on the beaches would be classed in our country as overweight or obese (but not morbidly, I don't recall ever seeing a French person that big). I do agree with a lot of what you say though - I think one of the reasons they keep slimmer is that they are more active, eat smaller portions and don't snack. The opposite of what many of us do in Britain!