How will Slippery Elm help me? Slippery elm is rich in nutrients and easy to digest, making it an excellent food during times of digestive discomfort. It is very mucilaginous, making a slippery substance when mixed with water. Traditionally it has been taken orally to soothe the respiratory and digestive systems. Ulmus rubra, is a species of elm native to eastern North America, and in times of famine, early American settlers used it as a survival food.