Its likely the Sorbitol. Sorbitol is a sweetener found in many things and for some, will cause IBS/diarrhea/gas. BK Onion Rings ALWAYS do this to me but I love them so I just make sure I know where ill be 2hrs after eating them lol. You could buy sugar-free gum that contains sorbitol and have her eat it to test the theory. The other possibility is fructans which is in all onions and could have the same reaction for someone.
Food Safety Report: Burger King, Freeport Road, Pittsburgh, PA, USA
Its likely the Sorbitol. Sorbitol is a sweetener found in many things and for some, will cause IBS/diarrhea/gas. BK Onion Rings ALWAYS do this to me but I love them so I just make sure I know where ill be 2hrs after eating them lol. You could buy sugar-free gum that contains sorbitol and have her eat it to test the theory. The other possibility is fructans which is in all onions and could have the same reaction for someone.
Sorbital AND the fructans actually,