Peppermint. Fresh peppermint (Menthea piperita) and peppermint oil capsules. Peppermint is used widely as a flavouring. It is also used as a herbal remedy for digestive problems. There is some evidence that it is an effective treatment for irritable bowel syndrome, nausea and bloating. The distinctive smell and taste of peppermint comes from menthol, a white crystalline organic compound chemically related to camphor.