without even beginning to explore the effects of big pharma upon our physical incarnations we must look at gmo's with their heavy pesticide load which appeared in the mid nineties. since then it seems 'my fellow americans' have become fatter and more stupid. could there be a correlation we might ask?
roundup is found in most water systems, and in most american's bloodstreams.
the bit below and link looks for more;

If you’re expecting a baby or considering starting a family soon, you’ve probably been reading up on how to give your child the best start in life. You probably wouldn’t dream of lighting up a cigarette or getting drunk while you’re pregnant, but you could very well be doing something that can be quite harmful to your unborn child if you’re being exposed to pesticides.
This isn’t a warning that only applies to farm workers; 33 million pounds of organophosphate pesticides were used in the U.S. in 2007 alone, putting countless people at risk.

 https://www.naturalnews.com/2018-06-10-pesticides-stupid-agricultural-chemicals-lower-iq-of-children.html