Is sust flu a symptom of rancid stuff?

I was told by someone that sust flu is a sign of rancid stuff, I'm about 90% positive this is complete bullshit I'm just double checking...What are your thoughts?

no, it has to do with the bacterias in the shit...it doesnt mean the shit is bad bro...rest and get throught it. good luck

it'll be ok.....it'll be ok.............

yeah it will be fine, its some bacteria, sometimes mexican products can do that to you, it will be cool.

Thanks for the input!!