Tutankhamen was buried with it to guard him from evil spirits in the underworld. Greek and Roman legionnaires chewed it to quench their thirst as they marched through the desert. Even the Kama Sutra recommended drinking it with milk and sugar as an aphrodisiac. Far from being an ancient nutritional fad, the root of Glycyrrhiza glabra—more widely known as licorice—remains one of today's most extensively used and scientifically investigated herbal substances.
Popularized by the candy that goes by the same name, licorice has been the subject of a wide variety of clinical trials.
In 1946, a Dutch pharmacist published a report on its effectiveness with ulcers, and research comparing the herb with medicines like Tagament continues in Europe. Licorice has been shown to soothe bowel and kidney irritations, cleanse the colon, and strengthen the liver. It provides a mild laxative effect and expels mucous from the lungs, making it helpful in the treatment of bronchitis, laryngitis, and sore throats—especially when taken as a tea.
When used topically, the glycyrrhetinic acid found in licorice root provides relief from canker sores, eczema, and psoriasis. According to herbalist Michael Castleman, author of The Healing Herbs, sprinkling powdered root onto clean sores may even help heal herpes.
These and other benefits reflect the root's ample cache of nutrients such as B and E vitamins, choline, biotin, and inositol. So far, researchers have identified an impressive list of glycosides and isoflavonoids, as well as triterpenoids, sterols, and amino acids. However, licorice's primary active ingredient is glycyrrhizin, a substance 50 times sweeter than sugarcane that appears to have anti-viral properties.
Another active ingredient, glycyrrhizic acid, is a natural anti-inflammatory compound that also acts as an anti-arthritic.
Unfortunately for black jellybean lovers, most licorice candy contains anise or other synthetic flavoring and therefore doesn't provide a healing effect. You'll find the real thing at health food stores, which generally carry both natural dried licorice root and licorice herbal supplements and extracts. Just be sure to consult with an herbalist before using licorice root therapeutically (or if you are pregnant or nursing), as high amounts of glycyrrhetinic acid have been shown to increase sodium and water retention, thereby dangerously elevating blood pressure and increasing cardiac dysfunction.
When it comes to licorice, too much of a good thing can be harmful. But taken in moderation, it is still the "fine medicine" that 17th-century herbalist Nicholas Culpeper extolled for ailments as varied as "hoarseness, heat of urine, and griefs of the lungs."