I was changing my 11 month old's diaper and noticed a red ring around his anus. I've seen it before but thought maybe it was just irritated from pooping. I'ved heard the red ring being referred to as an "allergy ring" but idk if that's what it is since he has no other symptoms (normal poo, no gas, no pain). He's breastfed and if it is an allergy then I know I will need to modify my diet (I'm already gluten free and corn free due to celiac). So my question is, is the red ring always a sign of a food allergy/intolerance? If it is, what food should I eliminate first?