@Tarmander didn’t Ray Peat mention about using juice during “fasting” or long time between food as preferable to “fasting”? I clearly remember him stating that which supports this idea. Forgive me, but I can not remember which interview I heard him talk about it.
Yes he said 24hs fast every now and then is not that bad and talked about doing fruit fasts too, like 600-800 calories from sugars (fruits/honey/juices) per day.