my aunt and uncle have a guava tree in the backyard. i also have been having amazingly huge and tough (physically) poops lately.

and conclusively:
"Guava leaves are used for medicinal purposes, as a remedy for diarrhea[citation needed], and for their supposed antimicrobial properties. The same anti-diarrheal substances which are useful in folk medicine may also cause constipation in the case of consumption of large amounts of guava fruits."