. When spicy food hits the tongue, it binds to TRPV1 receptors, which detect painfully hot things. Even though spicy food isn't always hot in temperature, the brain still receives a signal that the body is in heat-induced pain. Sweating, tearing up, and dripping snot are all ways the body tries to expel whatever is making that signal go off. But this might not be a guaranteed method for success. Congestion can often come from inflamed sinuses. Thus, even if mucus proliferates, the sinuses might not let it flow, and might cause the ingestion of spicy food to backfire. At least that's what Genovese theorizes.