system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are allergies more common in Eastern, Western and European countries but nearly non existent in Africa?

I'm from Africa and have had the opportunity to travel and meet a lot of people throughout the African continent but I have not met anyone during this time that has a food allergy and is a native African (not saying that they don't exist), is there some explanation as to why this is?
gpt
There is a theory that allergies can form when a young person grows up in a relatively sterile environment. The immune system, lacking anything to attack, becomes hypersensitive in some people. This isn’t to say that Africa is unclean, but your average African child is probably exposed to more pathogens than your average European child. I’m no expert, but this is what I’ve been told by an expert. I’m sure there are other variables or other theories.