I had bad GERD for years (it’s 85% resolved with weight loss, but can still flare up), and so many people would say “ah so you can’t eat spicy foods.” Nope–capsaicin had no effect on my heartburn and never did. But onions and tomatoes of any kind, if I wasn’t on a PPI or taking heavy chugs of something like Mylanta, would cause WWII in my stomach for the next 5-8 hours. Which sucked because onions and tomatoes are used in a huge % of foods I enjoy.