Colleagues laughed at me many times in public and said I was thin. What should I do?

You can't see anyone in the photo, can you?

As for being thin, I can only say that I am not fat, a little muscular, but not thin.

Laughing at colleagues is probably obesity. They want your figure, but, alas, they just can't reach it.

Sour grapes.

Just being laughed at and looking at them sympathetically in the future.