Wow - good for you! It's super rewarding to sometimes experiment with our diet and see what results it gathers. Sometimes quitting isn't even what is making us 'realize', but the 'starting again' (eating the food after 4 months of not eating it) that makes you realize what the food did to the body. For me it was grains: I felt fine not eating it, but when I started to eat it again my stomach was... not happy at all.
Could you point me to an article maybe that explains the influence of coffee on the gland? I could search myself, but sometimes asking for a reference article is really needed to get to the article. If it was a gradual insight that's okay, then I'll start googling myself :-)
Cheers!