I would like to think that the determination of whether or not a person is fat is left up to that person or their Dr.
My response to that type of characterization is, "So?".
Really, does it change how wonderful/awful a person is?
Fat, anemic, tall, short, skinny, one eye, cleft lip, all of that doesn't matter to the personality that is inside.
Tease me about being a jerk or rude or an ass or I cannot carry a tune.
Compliment me for being nice, thoughtful, or friendly or funny.
Don't charactarize me because of my skin color, my hearing, my accent.