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…
Same point in time where people started to get cell phones and be always connected to the internet.