There are two macro population health trends that suggest we are somehow poisoning ourselves at a large scale. Most people do not relate the two, but I personally wouldn't be surprised if they have related causes. The first is the Flynn effect, which was rising IQ levels decade over decade, which halted and then reserved for most Western nations around 1990s/2000s and is now declining: https://en.wikipedia.org/wiki/F…
We see obesity becoming increasingly normalized. People feel powerless to stop it and that we should just accept it.
It feels to me like there is something besides diet changes happening to us. That's part of it, but I wonder if microplastics or some kind of gut biome disruption is playing a role as well.