Compare life expectancy of first world (eg USA) with any third world nation’s population.
turn of the century (1900) US life expectancy for men was around 45-50, women closer to 60.
NOW it’s in the 70’s for both - look it up.
Third world? Where we were 125 years ago.
“Robust immune systmes” my white Irish butt. They STILL get a plethora of inbred genetic disorders, parasites and a host of other diseases Pandora never saw coming.
That doesn’t negate their strong immune systems.
I knew a missionary doctor couple many years ago who told me that. They told me they’d see people walking around with infections that would have killed any one of us long ago.
Additionally, it’s well known even here that the immune system not getting the practice it needs when it needs it is contributing to many health issues today, particularly the rise in allergies.