Black lentils are part of the lentils family (Lens culinaris), like brown, green, or red lentils, and they are much smaller than urad dal. Urad dal, often used in Indian and Asian cooking, is a bean, part of the Vigna family. It is a rich source of nutrition and helps boost energy. Urad dal is rich in fibers which help improves digestion. It may also help manage constipation by promoting bowel movements due to its laxative property.
