Autumn - I did say earlier, as I'm rather short (5'0) at size 8 I don't have a flat tummy and my thighs are a bit out of proportion, but not bad, still slim and healthy looking - at size 10 I'd have a gut and my face would start expanding, at size 12 i'd be proper fat - but then I have a very small frame. I don't have anywhere to 'put' any excess weight (sadly, it never goes on the boobs), if you're short an extra 5lbs shows so much more than the same extra weight on someone half a foot taller.
That doesn't mean that everyone who's a size 12 will look fat, but if you my height, you can't be above a size 10 and look slim. That's just too wide for the height.
I won't join in the "oh I eat fry ups every morning and cream cakes four times a day" because a) it's not true and b) it's not helpful to suggest that woman who are thin are only thin because they are naturally that way, it suggests to overweight woman that there's nothing they can do about their figures and c) you can be thin but very unhealthy if you don't have a good diet.
I do have to watch what I eat normally (early stages on pregnancy here so will eat whatever I can keep down), but that isn't a judgement on those who don't, I want to 'maintain' this weight not have to lose anything later on, it just seems easier to stay one size than go up then down again.
As for men - I tend to find men are unbelievely cruel and insulting about each other's weight, in a way woman would never be to each other's faces. And I also don't find fat/overweight men attractive.