weird that youre not getting the meaning of: "Strong laxative effect"
It's probably still a holdover from when San Francisco wasn't as crowded and had adequate access to public restrooms.
It's not really an issue in most of the country because there's at least adequate public restroom access.
You just say whatever you think with no supporting evidence.
Viewing ones unsupported opinions as more accurate than science (especially in a medical context) is considered delusional thinking by the psychiatric community and it's definitely indicative for a referral to a psychiatrist.