Rolfe
Adult human female
And it's also about portions... I have an obese colleague who is a vegan and very hands-on about her food preparation. Grows a lot of her own vegetables. The problem is that as healthy in principle as this food is, she eats a little bit more than she should is all.
And why wouldn't she? She's out there busting her ass doing all that weeding, which is hungry work. Exercise stimulates the appetite, and one of the demonstrated problems with introducing an exercise routine in an effort to lose weight is that a lot of people report it gives them more cravings, and that they need to eat more before achieving satiety, often out of proportion to the actual calories burned by exercise. She's a good example of this effect.
What is her attitude to her obesity? Is she a "happy fatty"? Does she have no health problems arising from obesity? Is she happy with the way she looks? Does she not mind the inevitable loss of mobility that obesity carries with it?
If she's happy, arguably the only reason to persuade her to change is to prevent health problems developing in future. Maybe she and those like her aren't the top targets of any change initiative.
And you're right about the exercise. Sometimes people think, well I just burned 75 calories, I can have that chocolate biscuit, so they do. And then they have another one.