My mom is one of those naturally skinny people who has never crossed out of the size 6 zone and even then, it was when she was 9 months pregnant with me. She was regularly called "chicken legs", "sticks", "skinny minnie" (which I think is equally damaging) all her life because of her build. She never talked about my weight other than to call me "Chunky Monkey" when I was a kid. As I grew older, it was never discussed at all.
That said, she sure as hell made derogatory comments about fat people whenever we were out. She was disgusted by the rolls, or made remarks on the quantity random people were eating or how unflattering their clothes were, etc. ALL.THE.TIME. It wasn't occasionally, it was constant. FInally, one day I turned to her and said, "You DO realize that I'm way fatter than the lady you just insulted, right?". She just looked at me like I was stupid. It was almost as if she never saw it on me. AND...she didn't stop the commentary. Sigh...