Mine‘s getting so accustomed to cold showers that I a) absolutely do not mind cold water for swimming etc. anymore and b) could not enjoy warm or hot showers anymore. They just weren’t nice at all.
I have a stomache of steel. Nothing will pass my digestive tract alive or intact. I never had any kind of stomache trouble and I can not puke. I ate every dish in south-east-asia that landet in front of me, even from some dirty streetfood shack in the middle of the burmese jungle. Most of the stuff would have killed the average middle european slob. Not me.
It even goes so far that I cannot use edibles. Which is funny, because all the growmies make fun of me now.
I have a pretty ironclad stomach, but not as strong as yours. I've been with my wife for 13 years and she's witnessed the horror that is me puking twice. And the first time came 4 years ago. My friends say it sounds like I'm "calling the dinosaurs" and it is very traumatic for me.
Cash money, that's where the real danger lurks. Even if you can drink bottled water and eat pre-packaged food, you have to handle the money. And that stuff is really, really nasty in some parts of the world.