I remember that Gaby mentioned that coffee gave her pain:
Maybe it's aflatoxins and not caffeine. In my father's village many people have bone pains and that place is famous for high humidity which stimulates mold which creates aflatoxins.
With time, I developed arthritis symptoms after coffee due to the aflatoxins. It didn't happened with organic aflatoxin-free coffees though. The aflatoxins create cross reaction with gluten-like proteins if I remember correctly.
Maybe it's aflatoxins and not caffeine. In my father's village many people have bone pains and that place is famous for high humidity which stimulates mold which creates aflatoxins.