1.Address the elephant in the room(pun intended),and point out problem areas and see what sort of plan or regimine they have planned out to deal with it.
2.Its important to be direct and let the woman feel your concern,it should be about more than the looks even though thats an important factor.
3.Use manipulation to let her know that the woman you fell in love with wouldn't be eating and living like she hated herself:henbron:
4.Put your foot down and only buy healthy food,and every time you see some bullshyt in your house throw it straight into the trash or eat it yourself. Let her have some cheat moments of course. But she has to know you are serious about this.
As an every man you should be able to transform yourself into a personal trainer if thats what your woman needs