This is super anecdotal and personal, but that quote sounds exactly like me. I'm Asian and didn't come from Greenland. Consuming sugar usually causes me those t

This is super anecdotal and personal, but that quote sounds exactly like me. I'm Asian and didn't come from Greenland. Consuming sugar usually causes me those things, especially in high dose (like eating a slice of cake). Fortunately I don't like cake or most sweet things in general, but if I do eat them, I can only very eat very little or I would feel all of those (diarrhea, abdominal pain, bloating). I'm also in my late 30s and borderline underweight (5'8" and 125 lbs). I have not grown out of this sucrose intolerance over the years.