Maybe your friend was referencing MSG? Makes me extremely thirsty hours later, and then I HAVE to "accumulate water in my body", on purpose, to satiate the unquenchable thirst caused by MSG
You're probably experiencing a sugar crash.
I suspect you don't experience the same after eating a bag of Doritos but they're absolutely loaded with MSG.. plus in all likelihood also sodium inosinate, sodium guanylate and who knows what else.
In fact, the fears around MSG seem to have some overlap with negative racial stereotypes:
Though to be fair it's a form of arms race, most US restaurants overdo it if the regional palette has become desensitized. It's not strictly a Chinese restaurant issue.
But many Chinese dishes on the menus are defined by their sweet and salty axis, and being in this environment they're pushed to the extreme.