OP here. Thanks all. Ok, so I'll give some more details:
I am the meal planner and the grocery shopper. I buy all healthy food, but he does insist on eating a sugary pastry for breakfast despite the fact that I cook myself eggs (mostly egg whites) and oatmeal every morning and offer to make him some too!
I DEFINITELY tell him straight up that he has gotten porky. And so has his mother. And all of his friends. And everyone else

I am not a naggy type so I don't bring it up constantly, but he knows my feelings on the matter.
Interestingly, he actually walks 2 miles to work everyday. So the porkiness is kind of surpisning.
I think it really comes down to the sugary pastry breakfast and eating crap for lunch/afternoon snack.
And to be fair, he is not obese. He's like 5'10 and I think like 180 lbs.
I think he just doesn't think it's a big deal. And there might not be much else I can do? It's not a dealbreaker by any means but I do miss the nice sharp jaw and also the nice clothes that are currently too tight..