Based on available evidence, licorice root may offer the most relevant support for: People with recurrent sore throats or mild upper respiratory irritation: Where its demulcent and local anti-inflammatory properties may provide symptomatic relief. People with digestive discomfort: Licorice root — particularly deglycyrrhizinated licorice (DGL) formulations — has a well-supported role in upper gastrointestinal comfort, which falls outside strict immune support but addresses a related use case. Those with inflammatory conditions: Where glycyrrhizin's cytokine-modulating properties may be relevant, though clinical evidence in healthy populations is thin. For healthy adults seeking general immune reinforcement during winter, the evidence base for oral licorice root is less compelling than for vitamin D or zinc, which have stronger RCT support in this context.

Licorice Root and Immune Support: Evidence Review

Licorice root immunity research is not new: Glycyrrhiza glabra and its close relatives have been used in traditional medicine across Asia and Europe for thousands of years, often for respiratory and immune-related complaints. Modern research has started to tease apart which constituents might be responsible for observed biological activity, with glycyrrhizin — the primary triterpenoid saponin — receiving the most scientific attention.

Immune Mechanism: How Licorice Root May Act

Glycyrrhizin and its aglycone metabolite glycyrrhetinic acid modulate immune activity through several pathways. In laboratory studies, glycyrrhizin has demonstrated direct antiviral properties, including inhibition of viral replication in herpes simplex and influenza models, and has been studied intravenously in clinical settings for hepatitis C (Manns et al., 2012). It also appears to suppress excessive cytokine release — a property studied in the context of inflammatory conditions — while simultaneously stimulating certain arms of innate immunity.

Licorice root also contains chalcones and flavonoids, including liquiritigenin and isoliquiritigenin, which show anti-inflammatory activity in cell models and may support immune regulation independently of glycyrrhizin.

However, most of the mechanistic work is from in vitro or animal models. Extrapolating directly to human oral supplementation requires caution, because oral bioavailability of glycyrrhizin is low: gut bacteria convert much of it to glycyrrhetinic acid before absorption, and the clinical concentrations achieved from dietary supplements are far lower than those used in intravenous research.

Infection and Illness Evidence

The most robust clinical evidence for licorice root in immune contexts involves its use in chronic hepatitis, typically via intravenous glycyrrhizin formulations rather than oral supplements. A systematic review found intravenous glycyrrhizin was associated with improvements in liver enzyme levels in hepatitis C patients, though evidence for prevention of viral illness through oral supplementation is limited (Manns et al., 2012).

For upper respiratory infections, evidence from oral licorice root supplementation is largely anecdotal or from small, uncontrolled studies. Licorice root is often combined with other herbs in traditional preparations, making it difficult to attribute specific effects to licorice alone.

A small number of studies in sore throat contexts have used licorice root gargle solutions and found some symptomatic relief — a plausible outcome given its anti-inflammatory and demulcent properties — but this is a localised effect rather than systemic immune enhancement.

Who Benefits

Based on available evidence, licorice root may offer the most relevant support for:

People with recurrent sore throats or mild upper respiratory irritation: Where its demulcent and local anti-inflammatory properties may provide symptomatic relief.
People with digestive discomfort: Licorice root — particularly deglycyrrhizinated licorice (DGL) formulations — has a well-supported role in upper gastrointestinal comfort, which falls outside strict immune support but addresses a related use case.
Those with inflammatory conditions: Where glycyrrhizin's cytokine-modulating properties may be relevant, though clinical evidence in healthy populations is thin.

For healthy adults seeking general immune reinforcement during winter, the evidence base for oral licorice root is less compelling than for vitamin D or zinc, which have stronger RCT support in this context.

Dose and Safety

OstroVit Licorice VEGE 90caps is available at maxfit.ee. Typical doses in research range from 1 to 5 g of dried root equivalent per day. The most important safety consideration with licorice root is its potential to cause pseudohyperaldosteronism through glycyrrhizin's inhibition of the enzyme 11-beta-hydroxysteroid dehydrogenase. This leads to sodium retention and potassium loss, which can elevate blood pressure and, at high doses, cause cardiac arrhythmia.

Regulatory guidance in several European countries recommends limiting glycyrrhizin intake to avoid adverse cardiovascular effects. People with hypertension, heart disease, kidney disease, or those taking diuretics or corticosteroids should exercise particular caution and consult a clinician before using licorice root supplements. DGL formulations, which have most of the glycyrrhizin removed, largely avoid this issue and are safer for longer-term use.

Honest Verdict

Licorice root has genuine biological activity at the mechanistic level, and some clinical evidence supports its use in specific gastrointestinal and hepatic contexts via intravenous administration. As an oral immune supplement in healthy adults, the evidence is more modest: it may provide some symptomatic relief for throat and respiratory irritation, but it is not a validated antiviral or immune booster in the way some marketing claims suggest. The safety profile requires meaningful attention, particularly around blood pressure and potassium levels, making it unsuitable for routine unsupervised long-term use at high doses.

FAQ

Is licorice root good for immune support daily?

Short-term use at moderate doses is likely safe for most healthy adults, but daily long-term use carries risks related to glycyrrhizin accumulation and blood pressure elevation. If you have cardiovascular or kidney concerns, choose a DGL formulation and limit duration.

Can licorice root prevent colds?

There is insufficient controlled clinical evidence that oral licorice root supplementation prevents cold or flu infections in healthy adults. It may ease throat symptoms once illness has begun, but this is symptomatic relief rather than prevention.

Does licorice root interact with medications?

Yes. Glycyrrhizin-containing preparations can interact with antihypertensive drugs, diuretics, corticosteroids, and digoxin. People on these medications should consult a pharmacist or clinician before using licorice root.

References

Manns, M. P., Wedemeyer, H., Singer, A., Khomutjanskaja, N., Dienes, H. P., Roskams, T., Wiegand, J., Zachoval, R., Haussinger, D., Petersen, J., Kullak-Ublick, G. A., Pape, G. R., & Rambow, A. (2012). Glycyrrhizin in patients who failed previous interferon alpha-based therapies: biochemical and histological effects after 52 weeks of treatment. Journal of Viral Hepatitis, 19(8), 537-546. https://pubmed.ncbi.nlm.nih.gov/22762137/

Fujioka, T., Kondou, T., Fukuhara, A., Tounou, S., Tsuchida, A., Kumagai, H., & Sato, K. (2003). Clinical efficacy of a glycyrrhizin suppository for the treatment of chronic hepatitis C: a pilot study. Hepatology Research, 26(1), 10-14. https://pubmed.ncbi.nlm.nih.gov/12787798/

Otake, T., Mori, H., Morimoto, M., Ueba, N., Sutardjo, S., Kusumoto, I. T., Hattori, M., & Namba, T. (1994). Screening of Indonesian plant extracts for anti-human immunodeficiency virus type 1 (HIV-1) activity. Phytotherapy Research, 9(1), 6-10.