When I was a teenager, I was the opposite of being overweight, I was super skinny and no matter what I tried, I could not gain weight.
Here's the thing; As a way of trying to cope with it, I would say that people should accept me the way I am, that they were cruel to judge, that they had no right to judge me by my weight. I tried to accept myself the way I am while not, but really I was kidding myself. I tried accepting that people make a joke of it, and go along with it, be a clown. Did this solve the problem? No.
So what did work? Well, the main thing was, I was determined to gain weight, somehow. I tried everything like calorie counting. Didn't work. Eating more fatty stuff. Didn't work. In fact everything that should have worked scientifically, didn't work. Going to the gym and eating more. Didn't work.
Being very creative as a thinker, I thought I would try to go within to try and solve the problem. I had been looking at the effects of fear and love, and the differences. So, I tried an experiment (I love trying experiments!)
a) Did I fear 'getting skinnier'? Yes. This would lead to a fear of not eating because I might lose weight.
b) Did I fear what others thought of me? Yes. So I feared not doing anything about it.
c) Did I fear rejection because of it? Yes. But this turned into a fear/avoidance of judgemental people.
So in my experiment, I tried this:
a) I am no longer going to fear getting skinnier, I am going to let go of that and if I lose weight I lose weight.
b) I love myself the way I am, because if I do that, I am going to become 'more' of what I love about myself.
Results:
I gained more weight in one month, than I did in 3 years, which was a miracle really. All I did was change how I think! And I have consistently been a more natural weight since then.
I think if we have a problem with ourselves, that is the problem. We come to fear ourselves. And out of that fear, and the power of fear, we become more of what we fear.
So let go of the fear. Don't blame anyone for judging you, when you already judge yourself. Love yourself the way you are. Do what you want, if it's eating this or that, do it! Why force yourself to do this or do that, to diet, only for that to go out the window when you stop the diet?
You see, when you love yourself the way you are, and you start to see what you love about yourself more, you start to change your habits. Yes you see that food that you thought was so delicious, but you just don't feel like eating it. Yes, you see that food you would never touch, but you want to eat it.
When fear is out the door, there is more room for faith, and if we just have faith in God, then he is the one saying, do this, or don't do that, and it 'feels natural' not forced. He can show us our most natural self, the way we were born to be. For me, it is being a natural weight, not skinny not fat. But maybe for some, it is being skinny or it is being fat, although I have always found that hard to believe. We all have a different view of what is natural. But overall, generally, there are a lot of reasons why being underweight or overweight are not natural/healthy.
Does God intend for us to be healthy? Well getting over the problems with our body, is the place where we become more able to express God. The body is a temple, and we are supposed to treat it with respect. Because if you lock yourself away because of a problem with it, in any way, even hidden from view while masquerading that you do not have a problem, (although God sees all) how can God use you as an instrument, as much as is possible if these initial blocks are gone?
God wants to use you as an instrument in your own world, to fix the problems you might have with yourself, or your mind. But he wants that, so that you can be an instrument in far greater works of faith.