Hurtful comment

So this morning my boyfriend was leaving my house and he was looking at me and said "are you getting bigger?" I looked at him like what are you talking about. He then asked again and said "you need to stop eating and start running." I was so hurt, I'm already insecure about my body and for him to say that makes even more insecure. Then when I told him he said he was only playing. I don't think that was funny.