What Is Licorice Root?
The root of the licorice plant (Glycyrrhiza glabra or Glycyrrhiza uralensis) has a long history of use in Eastern and Western systems of medicine. In traditional Chinese medicine, licorice root is referred to as "gan zao."
Why Do People Use Licorice Root?
In herbal medicine, licorice root is often combined with other botanicals to treat a range of health problems, including:
Benefits of Licorice Root
Although research on licorice's health effects is limited, studies suggest that the herb may be helpful in the treatment of prevention the following conditions:
1) Canker Sores
In a 2008 study, scientists found that an adhesive patch medicated with licorice root extract helped heal canker sores (also known as "recurrent aphthous ulcers"). After seven days of treatment with licorice, study members had a significant decrease in ulcer size. Volunteers who received no treatment, on the other hand, saw their ulcer size increase by 13 percent.
2) Functional Dyspepsia
When used in combination with other herbs, licorice root may ease the pain of functional dyspepsia (a chronic condition marked by upper abdominal discomfort). In a 2004 study of 120 people with functional dyspepsia, 43.3 percent of participants treated with an herbal formula (containing bitter candy tuft, matricaria flower, peppermint, caraway, and lemon balm in addition to licorice root) had complete relief of symptoms after eight weeks (compared to just 3.3. percent in the placebo group).
3) Colorectal Cancer
In preliminary research published in 2009, researchers discovered that treatment with glycyrrhizic acid (a compound found in licorice) helped prevent colorectal cancer progression in mice predisposed to the disease.
What Is Deglycyrrhizinated Licorice?
In large amounts, licorice containing glycyrrhizic acid or glycyrrhizin has been shown to cause high blood pressure and other adverse effects linked to heart problems (such as low potassium levels). Therefore, it's important to use only deglycyrrhizinated licorice (or DGL) extract, from which glycyrrhizic acid has been removed.
Despite the findings that glycyrrhizic acid may help prevent colorectal cancer progression, deglycyrrhizinated licorice has demonstrated effectiveness in the treatment of a number of conditions (including canker sores and functional dyspepsia).
Glycyrrhizin-containing licorice may interact with a number of drugs, including diuretics, insulin, laxatives, and blood-thinning medications.
Licorice should be avoided by people with renal of liver dysfunction, as well as by women who are pregnant or breast-feeding.
Where To Get It
Licorice products (including chewable tablets, capsules, tea, and powder) are available in most health-food stores.
Madisch A, Holtmann G, Mayr G, Vinson B, Hotz J. "Treatment of functional dyspepsia with a herbal preparation. A double-blind, randomized, placebo-controlled, multicenter trial." Digestion 2004;69(1):45-52.
Martin MD, Sherman J, van der Ven P, Burgess J. "A controlled trial of a dissolving oral patch concerning glycyrrhiza (licorice) herbal extract for the treatment of aphthous ulcers." General Dentistry 2008 56(2):206-10.
Zhang MZ, Xu J, Yao B, Yin H, Cai Q, Shrubsole MJ, Chen X, Kon V, Zheng W, Pozzi A, Harris RC. "Inhibition of 11beta-hydroxysteroid dehydrogenase type II selectively blocks the tumor COX-2 pathway and suppresses colon carcinogenesis in mice and humans." The Journal of Clinical Investigation 2009 119(4):876-85. doi: 10.1172/JCI37398.