@haidut thanks.
How long does it generally take (I know each case is different and unique in its own right) to overcome a relative caffeine intolerance? I do well on caffeine pills, but occasionally coffee can bring on a stress response and lower pulse and bring on hypoglycemia.
I am someone, like others, who is relatively unsure if stress (professional & relationship) brought on metabolism problems, or if metabolism problems made my stress feel much more significant than it truly is/was. I lean towards the latter, but the chicken or the egg debate is always interesting with the body and the brain.
The animal studies showed caffeine in HED of 200mg - 300mg daily reversed fatty liver in just 7 days. Not sure if the same holds in humans, but it seems to match the so-called "caffeine desensitization" occurring in about a week, which I thing is simply the liver being able to tolerate caffeine better. There is some adenosine receptor adaptation to the caffeine but the disappearance of jitters and such is probably due to improved liver function.