It's all psychosomatic. The hard of thinking go to India convinced they are going to get a stomach bug, and, hey presto! 8 hours later they're ****ting rusty bum gravy at high velocity.
Eat some yoghurt, go outside your hotel and eat street food with the locals and enjoy the experience.
When I went to Egypt as a kid we were warned not to eat or drink anything we bought locally. I said "screw that, I'm invincible" and ate some ice-cream with two other kids. All three of us became ill with the runs. In Guatemala after I bravely drank mosquito-infested water in the jungle I had dodgy insides for months.
Well, as in all things, ymmv, as I believe our colonial cousins have it. However, far better to live a day as a lion than a lifetime asa sheep, surely?
I once ate some dodgy meat on a stick in a market on the shore of Lake Victoria, which left me with crippling griping cramps for 18 months. But I never shít myself.
Well, from the description of colleagues that have been there before me; it appears I would miss out on abject poverty, appalling misogyny, traffic jams of unbelievable proportions and, as you pointed out, debilitating stomach issues which could run on for months thereby pretty much ruining my day to day existence.
I'll take the sheep's existence, thanks very much.