Licorice root (Glycyrrhiza glabra) is a traditional herb with clinical evidence supporting its use for digestive discomfort and mild soothing of the throat and upper respiratory tract, primarily in its deglycyrrhizinated (DGL) form, which removes the compound responsible for licorice's most significant safety concern: glycyrrhizin-related blood pressure and potassium effects. This guide covers the mechanisms, evidence, dosing, and safety in depth.
Quick Facts
- Category: Root herb (Fabaceae/legume family)
- Key constituent: Glycyrrhizin (removed in deglycyrrhizinated/DGL forms)
- Key benefits: Digestive comfort, throat/mucous membrane soothing
- Important distinction: DGL (deglycyrrhizinated) licorice avoids glycyrrhizin's blood pressure/potassium risks
- Common forms: DGL chewable tablets, tea, whole-root extract
What Is Licorice Root?
Licorice root comes from the Glycyrrhiza glabra plant and has a long history of medicinal and culinary use across European, Middle Eastern, and East Asian traditions, distinct from most licorice-flavored candy sold today, which typically uses anise oil rather than real licorice root extract. The plant's most notable compound is glycyrrhizin, a sweet-tasting triterpenoid saponin roughly 50 times sweeter than sugar, which is also responsible for licorice's most significant safety concerns when consumed in large amounts over time. Because of this, a processed form called deglycyrrhizinated licorice (DGL), which has most of the glycyrrhizin removed while retaining other beneficial flavonoid compounds, has become the preferred form for regular supplemental use, particularly for digestive support.
Mechanisms of Action
Licorice root's flavonoid compounds, which remain present in DGL preparations, are believed to support the stomach and intestinal lining by increasing the production of protective mucus and supporting mucosal blood flow, which is the proposed mechanism behind DGL's traditional use for digestive discomfort and occasional stomach lining irritation. Whole (non-deglycyrrhizinated) licorice's glycyrrhizin compound has a distinct mechanism: it inhibits an enzyme (11-beta-hydroxysteroid dehydrogenase) that normally deactivates cortisol in the kidney, allowing cortisol to act on aldosterone receptors, producing effects similar to excess aldosterone, including sodium retention, potassium loss, and increased blood pressure; this is the mechanism responsible for whole licorice's significant safety considerations discussed below, and is specifically why DGL, with glycyrrhizin largely removed, is preferred for regular use.
Evidence-Based Benefits
Digestive discomfort and dyspepsia. Evidence level: Established. Clinical trials, including studies on DGL specifically, show benefit for functional dyspepsia and stomach lining discomfort, with DGL considered a reasonably well-supported traditional digestive support option that avoids glycyrrhizin's safety concerns.
Cough and throat irritation. Evidence level: Promising. Licorice root's demulcent (soothing, coating) properties are traditionally used for cough and sore throat, with some clinical support, particularly in combination herbal cough formulas, though standalone licorice trials for this specific use are more limited.
Skin conditions (topical). Evidence level: Promising. Topical licorice extract, including licochalcone and glabridin compounds, has shown benefit for certain inflammatory skin conditions like eczema and hyperpigmentation in clinical studies, an application distinct from oral digestive use.
Hormonal effects (whole licorice, glycyrrhizin-containing). Evidence level: Established (as a safety consideration, not typically a sought benefit). Whole licorice's well-documented effect on cortisol/aldosterone pathways is primarily discussed as a safety consideration rather than a therapeutic benefit for supplement purposes, given the risk of blood pressure elevation and potassium loss with regular, higher-dose whole licorice consumption.
Dosage & Timing
For digestive support, DGL chewable tablets are commonly dosed at 380-760mg, chewed before meals, typically 2-3 times daily. Whole licorice root tea or extract, if used, should generally be limited in both dose and duration given glycyrrhizin's safety profile; health authorities in several countries have recommended limiting glycyrrhizin intake to no more than 100mg daily for the general population, with lower limits suggested for at-risk groups. There is no official Recommended Dietary Allowance for licorice root.
Interactions & Contraindications
Whole (non-deglycyrrhizinated) licorice can raise blood pressure and lower potassium levels with regular, higher-dose consumption, which can be dangerous when combined with blood pressure medications, diuretics (particularly potassium-wasting diuretics), digoxin (where low potassium increases toxicity risk), or corticosteroids. Individuals with hypertension, heart disease, kidney disease, or those who are pregnant should avoid whole licorice root and glycyrrhizin-containing products, and should choose DGL instead if licorice-based digestive support is desired, since DGL does not carry these specific hormonal risks. Licorice, even DGL, may interact with certain medications processed by the liver, so discussing use with a healthcare provider or pharmacist is reasonable for anyone on multiple medications.
Safety, Side Effects & Warnings
DGL is generally well tolerated with a good safety record for digestive support use, since removal of glycyrrhizin eliminates the primary safety concern associated with whole licorice. Whole licorice root, by contrast, carries meaningful safety considerations with regular or high-dose use, including elevated blood pressure, low potassium (hypokalemia), fluid retention, and, in case reports of very high or prolonged intake, more serious cardiac and muscular effects related to severe potassium depletion. Pregnant individuals should avoid whole licorice root, as some research has associated high licorice consumption during pregnancy with adverse outcomes, including preterm birth in certain studies.
ⓘ For regular digestive support use, deglycyrrhizinated licorice (DGL) is strongly preferred over whole licorice root, since it retains beneficial soothing flavonoids while removing glycyrrhizin, the compound responsible for licorice's blood pressure and potassium-related safety concerns.
Frequently Asked Questions
What is the difference between licorice root and DGL?
DGL, or deglycyrrhizinated licorice, has had most of the glycyrrhizin compound removed through processing. Glycyrrhizin is responsible for licorice's blood pressure and potassium-related safety concerns, so DGL retains licorice's soothing digestive properties while avoiding these specific risks, making it the preferred form for regular supplemental use.
Can licorice root raise blood pressure?
Yes, whole (non-deglycyrrhizinated) licorice root, when consumed regularly in meaningful amounts, can raise blood pressure and lower potassium levels due to its glycyrrhizin content, which affects cortisol and aldosterone pathways. This is why DGL is recommended over whole licorice for most regular supplemental uses.
Is licorice root candy the same as licorice root supplements?
Most licorice-flavored candy sold today uses anise oil for flavoring rather than actual licorice root extract, though some traditional or specialty licorice candies do contain real glycyrrhizin-containing licorice extract and could theoretically carry the same safety considerations if consumed in large quantities regularly.
Is licorice root safe during pregnancy?
Whole licorice root containing glycyrrhizin should be avoided during pregnancy, as some research has linked high licorice consumption during pregnancy to adverse outcomes. Pregnant individuals should consult their healthcare provider before using any licorice-containing product, including DGL.
Scientific References
- Raveendra, K. R., Jayachandra, Srinivasa, V., et al. "An Extended Use of 341mg Aqueous Extract of Glycyrrhiza Glabra (GutGard) in the Treatment of Functional Dyspepsia." Evidence-Based Complementary and Alternative Medicine, 2012;2012:216970.
- Omar, H. R., Komarova, I., El-Ghonemi, M., et al. "Licorice Abuse: Time to Send a Warning Message." Therapeutic Advances in Endocrinology and Metabolism, 2012;3(4):125-138.
- Strandberg, T. E., Andersson, S., Jarvenpaa, A. L., McKeigue, P. M. "Preterm Birth and Licorice Consumption During Pregnancy." American Journal of Epidemiology, 2002;156(9):803-805.
- Isbrucker, R. A., Burdock, G. A. "Risk and Safety Assessment on the Consumption of Licorice Root (Glycyrrhiza sp.), Its Extract and Powder as a Food Ingredient, With Emphasis on the Pharmacology and Toxicology of Glycyrrhizin." Regulatory Toxicology and Pharmacology, 2006;46(3):167-192.
Disclaimer
This article is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. It does not constitute medical advice and is independent of any specific product or brand. Always consult a qualified healthcare provider before beginning any new supplement regimen, particularly if you are pregnant, have high blood pressure, heart disease, kidney disease, or are taking diuretics, digoxin, or corticosteroids.
