I went into this a little on the Yoga thred a few weeks ago. As a teenager I was totally depressed about my body and not living up to the standards that men (then and in that country) liked. I wanted to be white and blonde and slim, which was what all the men ran after in a country where the people were 95% black and brown. Yes, I wanted desperately to be white, so as to get a good man. Instead I got fat and and had an eating disorder (basically stuffing my face) and so got fatter and (in my view, and theirs) even more unattractive. And all I wanted was to be loved.
I discovered that men don't care if you are fattish, if they want to screw you and screw you over. And if you were in love (I mostly was: it was love I yearned for, not sex) with them that could be devastating. Basically thinking that if a man desired me he loved me, which we all know is the game many of them play, because they see our weakness, that longing for love, and take what they can get. It's the big deception that many of us fell for and still fall for.
As I said in that thread, discoving yoga changed all that; I got slim in a few months but more important was a change in attitude, in that I no longer identified with my body, in thinking, because my body is fat and ugly (in my view) that's what I am, and so I can never be loved (by men).
It was no longer "this (body) is me!" but "this (body) is my home, I live in it". I became more objective towards it, and so I could deal with it by eating healthy foods, exercise (yoga) etc. And so it took care of itself, and my weight sorted itself out.
I don't think that constantly telling obese people, oh, but you're beautiful, just as you are!!!! is helpful. They KNOW it's not true. They still hate their bodies, even when they repeat it day and night and try to pretend they "love themselves" just as they are. It's not love at all imo.
For me it was an inner growth, in which I could kind of dissassociate with the body and at the same time look after it and keep it healthy, while seeking something in myself, in my mind, that WAS and IS healthy and beautiful. Cultivating an attitude of knowing and disovering who I really was: someone, a person, who inhabited this body and who could feel good within it, no matter what it looked like and no matter if men were attracted to it or not.
I've kept up that attitude all through the decades, which is why I found it much easier to accept the body's ageing.
I see older women complainaing and worrying all the time about no longer being "sexy" and how to keep themselves "sexy" well into their 70's and 80's. I think there's a basic problem with the word "sexy". It has become a synonym for beautiful, whereas it basically means being sexually attractive. I don't think that is helpful for our self esteem when we are ageing.