Is it ok for my husband to crack jokes about my diet and/or figure?

When we met 7 years ago I was a size 2 and remain a size 2 today. I have definitely fluctuated about 10 lbs up and down, but always fit into the same clothes. Before he would mention I was too skinny. Now whenever I eat something he doesn't approve of, he'll warn me about gaining weight. He even went so far as to say "No one likes fat chicks." He is a very loving person otherwise, but I can't help but be very bothered by this and he sees nothing wrong with it because "it's just a joke." I think that weight/figure is never an appropriate topic for a joke. I also don't appreciate his suggestion that he might not be with me if I don't stay exactly as I am, which is unrealistic.