As that guy said, your body adapts to whatever you do. Shifting to OMAD, the first day or two is a bit rough but later you easily become able to eat 2k calories in "one sitting", provided you have the food available. It's called "one meal a day", but is actually understood to be "eating in a small window of time", which can be between 1-4 hours long, well enough time to eat some, take a digestion break / go for a small walk, then eat again.
He mentioned nicotine, so I should say fasting of any short, from a physiological viewpoint, doesn't care if you consume nicotine or caffeine or water. You can go without water for a day if you just don't like drinking water, but doing so "because you're supposed to" is a) just ramadan nonsense and b) likely done to further test willpower / spiritual stuff (which to be fair is the entire point of ramadan anyway, so in that sense it's fine, but physically it's stupid, especially for a desert people).
auto is greek for self
phage is greek for eating
it directly translates to "eating of the self", and is what the macrophages (see that same root) and other immune cells do to clean up the body.
I know you're just shitposting but I like linguistics too much to play along sorry.