You know what, I think there is something to this.
I noticed it myself when I´m in the US. The food is harder on my stomach. Every time I visit I get weird stomach discomfort for the first couple days. Then a quick "flush" (if you know what I´m saying...) and then I´m ok.
A friend of mine lives in Vegas now. His wife is from France. Ever since they moved to the US she can´t eat anything that´s non organic. Any meats, dairy, breads... she eats that has been bought at Walmart e.g. will cause her body to react in some way. Rashes, bloating, diarrhea... At home in France she has no issues whatsoever.
The truth shall set you free! France has been the toughest on companies like Monsanto from being allowed to enter Europe. I pray the corruption doesn't shift overseas and y'all start to get poisoned food!