The Science of Fasting
I switched from 23 hour and longer fasts twice a week to 16:8 recently and am having great results. The longer fasts almost made me feel like I was developing an eating disorder.
I received a notification the other day from Zero (the fasting app I use to track my progress) and one of their medical staff was saying that it may not be a good idea to do multi-day fasts right now. Didn't read the whole article because I'm not doing long ones anymore, but they seemed to be recommending shorter durations to aid in immune system responses, etc. Will see if I can find it and detail more about it.