TLDR at the end.
Som Tam is my favourite spicy dish. The one in the photo is from Zaab Eli, a chain restaurant in Bangkok. They used to have spice levels from 0-5 and now it's non spicy to very very spicy, but the secret to ordering how spicy you want the dish is to just specify the number of chillies (in this case 30 ( prik sam sip met)). This avoids any confusion, as very spicy for one person, may be non-spicy for another. If you can eat this dish on its own I'd class your spice tolerance as pretty high. I think most cases of getting an upset stomach are caused by masking the chilli, usually by having oily or fatty accompaniments. For example if I ate the same salad with a glass of milk, it would not taste spicy & I would not get the endorphin rush that I crave.
Thai green & red curries are not spicy dishes. The clue is in the coconut milk, which ameliorates the spice. When I do make them at home, if I were to add enough reaper powder to make them taste spicy, I'd be guaranteed an upset stomach. If you want spicy green curry, get it from a restaurant that does dry green curry. This is basically a stir fry with the curry paste & you will be able to taste the chilli.
Beware of cheesy pizza. I had a rare upset stomach after eating a pizza with my favourite reaper sauce. Only when I finished eating, did I realise that I'd used nearly half a bottle.
Although tasty, be mindful of crispy chilli in oil, unless you have a good idea what your spice tolerance is or at least ask yourself, would I be happy eating this food with the equivalent number of heaped spoons of dried chilli.
TLDR : Don't eat a lot of fat or oil with chilli or you won't taste it & your stomach will suffer.
by somnab