No, it’s not an official term, but it’s widely popular. It occurs in — who else? — American visitors, tourist or otherwise, who come to France and can’t handle some of the food. I’ve said before that French food is, in general, better than what you can find in the States; part of that is because the food here is much richer, much more natural, much less processed. It can be like making the jump to whole milk when all you’ve ever had in your life was skim milk. Sometimes, your stomach doesn’t agree with the richness; sometimes, it doesn’t agree with some of the naturally-occurring (and, it should be said, perfectly healthy) bacteria that gets zapped out in American processing (see: cheese). Either way, your system only wants to get rid of whatever you just ate. FOREIGN FOOD! OH NO!!!
Now, symptoms of this, shall we call it a syndrome, range from a slight upset stomach to such severe pains and other gastrointestinal problems that you have to go to the ER. It also leaves anyone with a French-adjusted stomach playing nurse for a while. I’m not saying that I’m annoyed by this, but when two people that I love very dearly visit me within three weeks of each other and both get sick, one landing in the hospital, it makes me wonder if it’s something I did. Gah. I promise I’m not trying to poison anyone!
On the plus side, I now know enough about French hospitals AND pharmacies to figure out the system again, if need be. Yippee.
(Disclaimer: American-stomach is just one theory of why both of these people got sick. No one really knows.)