Cumin is an herb. The seeds of the plant are used to make medicine. People take cumin for digestion problems including diarrhea, colic, bowel spasms, and gas. Cumin is also used to increase urine flow to relieve bloating (as a diuretic); to start menstruation; and to increase sexual desire (as an aphrodisiac). In spices, foods, and beverages, cumin is used as a flavoring component.