Going out food is also a potential culprit for hangovers without alcohol. I used to live in a place where domino’s was the only place that delivered and it took me until about the third non-drinking hangover I got after getting pizza to realize it was the salt.

That’s also why people report headaches, nausea, and dizziness after eating MSG, imo. It’s not anything to do with the MSG itself, just dehydration from the sodium that would cause the same issues if they’d ingested it in the form of table salt.