Specifically, Jenassa won't regenerate her health after battle, and I think I might have had this problem with Faendal as well - he died a little too easy, imo.

I've tried to wait, FT, dismiss, enter new cell, using the console to disable/enable, trying the "kill" command (which sometimes works, according to UESP). Since I have UFO, I've tried to ask her to train, but that didn't help either.

I finally gave up and console commanded myself a healing staff (this character doesn't know Healing Hands, and I don't want to use Restoration with him, either). However, it just fixes the symptom without solving the actual problem.

Any suggestions? I have some mods that can affect followers, most notably UFO. When I read on UESP, it seems like this problem exists in the vanilla game, though.