Tread lightly. Your relationship is still relatively new so chiming with seemingly helpful suggestions may come back to haunt you later.
Support him by listening to him vent about it and only address what he has to say. If he asks you what should he do you need to becareful of your answer, maybe a generic one for now like, "Idk, but I'm sure you'll figure this out eventually"
My gf has a boat load of problems with her adult children and even we've been together for 3.5 years I still tread somewhat lightly when it comes to them.
It is not okay for an alcoholic to get drunk once in a while.
So do not tell a food addict it is okay to eat like sh*t once in a while