Arrowroot comes from a plant. Arrowroot’s root and rhizome (underground stem) are used as a starch source. It’s also used to create medicine on occasion. Arrowroot is claimed to treat irritable bowel syndrome (IBS), diarrhea, various stomach, and intestinal diseases, painful gums, and other illnesses. However, there is little scientific evidence to back up many of these claims. Arrowroot is found in a variety of cuisines, including cookies. It’s also utilized as a cooking ingredient.