If they are not in my household then I don't care. I don't accept fat sims in my household though. If they start putting on weight, then I shackle them to a treadmill. It used to be that sims would become almost insta-hefty on turning adult, but I haven't noticed that happening lately.
One problem that I think came with CL is that the game almost always generates sims in pear shape now. I rarely see any other body type spawned. So if one of my sims happens to marry a spawned townie then I usually have to change the body type to something other than pear.