[naasking]

Gastrointestinal issues are almost never due to the last thing you ate, unless you're living in a third world country. It's usually the highly contagious norovirus, which you typically get from shared bathrooms and door handles. Most people just call it food poisoning because that's just how our brains work, as a protective bias.

[oliv__]

Citation needed

[naasking]

See outbreaks:

https://www.cdc.gov/norovirus/trends-outbreaks.html

50% of food borne illnesses are already caused by norovirus. Now look at the graph above, and notice that non-food based transmission of norovirus is almost 8x higher.

Differentiating between norovirus from actual food poisoning is not too difficult either.