Provided herein are compositions, for example: oral rehydration compositions, beverages, food items, methods and uses, which utilise resistant starch to prevent or treat dehydration, including dehydration which is caused by diarrhoea. Beverages, food items and oral rehydration solutions including a resistant starch, which are suitable for aiding in the maintenance and restoration of hydration levels in individuals undertaking physical activities, including sports, are also disclosed.