Since he is fat himself, I wonder if a snarky remark about him needing to lose weight to prevent diabetes would shut him up. I am not able to come up with anything creative, but I wonder if giving him a taste of his own medicine might be all that is needed at this juncture. I do not know if you would be up for that, but mentioning that fatness is men correlates with low testosterone levels which in turn correlates with impotence might get a rise from him, no pun intended. Men: Is Obesity Affecting Your Sex Life? - Obesity Action Coalition.