There have been reports of YouTubers I watch getting sick after eating food in third world countries. However, these countries are also home to a large number of people who do not get sick from eating the same food. I think this suggests that the locals may have developed stronger immune systems. What do you think?
Not necessarily, it is likely that a tourist is just not used to these specific pathogens. While the people living there are used to them. So their immune system isn’t better per se just more adapted to the environment.