this is a great read but you know here is the US people drink insane amount of coffee i growth up in the Caribbean and people just take one cup of expresso once a day maybe twice but a very small amount .
Caffeine withdrawal is no joke. I think most people just drink coffee so regularly they never experience it.
I spent years drinking 2 to 4 cups daily and also smoking cigars. I didn’t notice much from caffeine, as I’d gotten into it in high school to wake up for cross country practice. We were running by 6am.