The simple answer is that humans eat whatever they can in order to survive. The more choice they have, the more picky they become.
It also depends on the relative nutritional value of the foods - just because humans can eat something without getting sick / ill doesn’t mean that they are necessarily getting anything good out of the foodstuff.
So in short, more-or-less anything of nutritional value is eaten by humans. If it’s not eaten everywhere, it’s just because the humans in that location have found a substitute what they find more palatable…
Hope that helps…