Somer
Sauna is great while fasting. Be sure to drink LOTS of extra water in general, and for sure if you are doing the sauna thing.
I don't know enough about fatty liver disease to be able to answer that one. However, even diabetics can fast on the MC, using the blackstrap molasses protocol outlined in the book. If your condition is serious you really ought to consult a health pro prior to fasting.
Merry Christmas!
Somer