Due to a rare disorder, Kerry Trebilock, 21, has eaten her way through 4,000 washing-up sponges and more than 100 bars of soap.The dental nurse from Cornwall suffers from pica, a condition that drives people to eat inedible objects.Trebilock spices up her tasteless snacks with sauces and dips such as mustard, BBQ sauce and ketchup - or jam and honey for a sweet fix.