Limiting eating to, say, daytime hours or a certain window of time like 14-16 hours would seem to be the way people were meant to eat because that'd just eliminate the night hours, so if a "fast" was like, don't eat during the night hours, that just seems normal to me.
But except for spiritual reasons going too long without eating in a 24 hour period doesn't seem in my opinion to be necessary or a good thing unless, say, a person was ill with the flu or something where it could be helpful (I'd think) and it could really be harmful for people with low blood sugar problems, in my opinion, and for me that would make all my physical problems worse.
Having too low a blood sugar level as can happen with some diabetics, sometimes during the night, can cause death, so if fasting, it'd seem like a good idea to make sure with the doc that it's ok dokey to do it.
Not trying to change anyone's mind 'bout anything, just commenting.
I've tried to "fast" between three regular meals and for me not even that works. I personally work best with mini meals all day long and at night I remain ok until morning just naturally.
Everyone is different.