Pretty sure there's some age related effects too. Over the last ~20 years I've gone from being happily able to drink coffee after dinner, through not being able to drink it after 5pm or so, and now to having the espresso machine automatically shut off at 2:30pm - otherwise my sleep quality plummets.
I'm 57 now, I started noticing poor sleep related to late night coffee in my mid 30s. I do got fairly hard earlier in the day though, I've usually had 4 double espressos (somewhere between 17-21g of beans) by mid morning, and usually another one or two before my current self imposed 2:30pm cut off.
I'm 57 now, I started noticing poor sleep related to late night coffee in my mid 30s. I do got fairly hard earlier in the day though, I've usually had 4 double espressos (somewhere between 17-21g of beans) by mid morning, and usually another one or two before my current self imposed 2:30pm cut off.