Taiwan obese students are very depressed especially during puberty

Taiwan obese students are very depressed especially during puberty

There are several heavily overweight students in my classes who seem to be really depressed.
I teach all ages here in Taiwan and noticed that as long the kids do not reach puberty, there is not much of a problem with that. Once they, however, become more self-aware, they hit a wall.
When I asked one of the chubby students to participate in activities such as writing on the white-board, he seemed to hate me for ever.

What are these parents thinking? Don't they know how much suffering they cause their kids to endure.

The thing is that I have fat kids at younger ages and they do well. They are happy and love to participate all play activities. But once they hit puberty it's over.

I carefully write into the communication book that their kid needs more exercise to gain more body-control etc. . Once, I wrote your kid needs a healthier diet. This child was just getting too fat and I saw her father pretty much every day sticking disgustingly greasy looking foot into her mouth. She became more and more a terribly depressed child.


The biggest problem I see here right now is that they do not want to participate in any physical activities where they are exposed to the looks from others. Even going to the white-board can be a problem. 

How do you deal with this issue?  Do you just keep quiet?

What are the parents thinking?