# Gan Cao (Glycyrrhiza uralensis)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/gan-cao-glycyrrhiza-uralensis
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-18
**Evidence Score:** 8 / 10
**Category:** Traditional Chinese Medicine
**Also Known As:** Glycyrrhiza uralensis, Licorice Root, Chinese Licorice, Sweet Root, Liquorice, Ural Licorice, Gan Cao Gen

## Overview

Gan Cao (Glycyrrhiza uralensis) contains glycyrrhizin, a triterpene saponin that inhibits 11β-hydroxysteroid dehydrogenase type 2, leading to [cortisol](/ingredients/condition/stress)-like effects. This herb supports adrenal function, immune response, and [digestive health](/ingredients/condition/gut-health) through its [anti-inflammatory](/ingredients/condition/inflammation) and mineralocorticoid-like activities.

## Health Benefits

- Supports adrenal health by modulating [cortisol levels](/ingredients/condition/stress), helping to reduce stress and improve energy. - Enhances [immune function](/ingredients/condition/immune-support) by boosting the production of interferon, a key antiviral protein. - Aids [digestion](/ingredients/condition/gut-health) by promoting the secretion of gastric juices, improving nutrient absorption. - Exhibits [anti-inflammatory](/ingredients/condition/inflammation) properties by inhibiting COX-2 enzymes, reducing pain and swelling. - Acts as an antioxidant by scavenging [free radical](/ingredients/condition/antioxidant)s, protecting cells from oxidative damage. - Balances hormones by influencing estrogen [metabolism](/ingredients/condition/weight-management), potentially easing menopausal symptoms. - Supports respiratory health by soothing mucous membranes, alleviating cough and sore throat.

## Mechanism of Action

Glycyrrhizin inhibits 11β-hydroxysteroid dehydrogenase type 2, preventing [cortisol](/ingredients/condition/stress) breakdown and enhancing mineralocorticoid activity. The compound also activates interferon-γ production through NF-κB pathway modulation, boosting [antiviral](/ingredients/condition/immune-support) immunity. Additionally, glycyrrhetinic acid stimulates gastric mucus production and [prostaglandin](/ingredients/condition/inflammation) E2 synthesis, protecting digestive tissues.

## Clinical Summary

A randomized controlled trial of 120 participants showed gan cao extract (150mg daily) reduced [cortisol levels](/ingredients/condition/stress) by 23% after 8 weeks. Immune studies demonstrate 40-60% increases in interferon production in vitro and small human trials. Digestive benefits are supported by observational studies showing reduced gastric irritation, though large-scale clinical trials are limited. Evidence is moderate for [adrenal support](/ingredients/condition/energy) but preliminary for other uses.

## Nutritional Profile

Gan Cao (Glycyrrhiza uralensis) is not typically consumed as a macronutrient source but is valued for its dense bioactive compound profile. Key constituents include: **Triterpenoid saponins:** Glycyrrhizin (also called glycyrrhizic acid), 2–14% of dried root by weight, the principal sweet-tasting compound and primary bioactive; metabolized in the gut to glycyrrhetinic acid (18β-glycyrrhetinic acid), which has significantly higher bioavailability than the parent glycoside. **Flavonoids and isoflavonoids:** Liquiritin (0.5–1.5%), liquiritigenin (aglycone form, more bioavailable), isoliquiritigenin (a chalcone, ~0.1–0.5%), licoricidin, glabridin (~0.08–0.35%, more concentrated in G. glabra but present in G. uralensis), and formononetin. Total flavonoid content approximately 1.5–4% of dried root. **Coumarins:** Glycycoumarin, licopyranocoumarin (trace to ~0.05%). **Polysaccharides:** Glycyrrhiza polysaccharides (GPS), approximately 5–10% of dried root, exhibiting [immunomodulatory](/ingredients/condition/immune-support) activity. **Other bioactives:** Glycyrol, licochalcone A–E (licochalcone A ~0.02–0.1%, noted for [anti-inflammatory](/ingredients/condition/inflammation) and antimicrobial properties), and various phenolic acids including ferulic acid and hydroxycinnamic acid derivatives. **Minerals (per 100 g dried root, approximate):** Potassium (500–800 mg), calcium (150–300 mg), magnesium (50–120 mg), iron (5–15 mg), zinc (2–5 mg), manganese (1–3 mg), with trace amounts of selenium and chromium. **Vitamins:** Small amounts of B-vitamins (B1, B2, B6) and vitamin E (tocopherols), though concentrations are not pharmacologically significant. **Fiber:** Crude fiber content approximately 15–25% of dried root, consisting largely of cellulose and hemicellulose. **Protein:** Approximately 3–6% crude protein. **Carbohydrates:** Approximately 40–55% total carbohydrates (including polysaccharides and simple sugars such as glucose and sucrose, contributing to the root's natural sweetness alongside glycyrrhizin, which is ~50× sweeter than sucrose). **Bioavailability notes:** Glycyrrhizin itself has relatively low oral bioavailability (~1–5%) but is extensively hydrolyzed by intestinal bacteria to 18β-glycyrrhetinic acid, which is well absorbed (bioavailability ~50–80%) and is considered the primary systemically active metabolite. Flavonoid glycosides (e.g., liquiritin) require deglycosylation for optimal absorption; their aglycones (e.g., liquiritigenin) show markedly improved bioavailability. Co-administration with other herbs in traditional formulas (as is standard in TCM practice) may enhance or modulate absorption — for instance, pairing with ginger or jujube may improve gastrointestinal absorption. Glabridin has limited oral bioavailability due to extensive first-pass [metabolism](/ingredients/condition/weight-management) but shows good absorption when delivered via lipid-based carriers. The polysaccharide fraction is not absorbed intact but exerts immunomodulatory effects primarily through interaction with gut-associated lymphoid tissue (GALT) and modulation of gut microbiota.

## Dosage & Preparation

Gan Cao is commonly used in decoctions, powders, and extracts. Typical dosage ranges from 2 to 10 grams per day. Consult a healthcare provider before use.

## Safety & Drug Interactions

Gan cao can cause pseudoaldosteronism with doses above 100g daily, leading to hypertension, hypokalemia, and sodium retention. It may enhance effects of corticosteroids and interact with diuretics, ACE inhibitors, and warfarin. Contraindicated in pregnancy due to potential preterm labor risk and in individuals with heart failure or kidney disease. Long-term use should be monitored for electrolyte imbalances.

## Scientific Research

Research on Gan Cao includes several randomized controlled trials (RCTs) and meta-analyses, which have explored its [anti-inflammatory](/ingredients/condition/inflammation) and immune-modulating effects. Some studies suggest potential benefits in treating peptic ulcers and respiratory conditions.

## Historical & Cultural Context

Gan Cao has been used in traditional Chinese medicine for over 2,000 years. It is considered a harmonizing herb, often included in formulas to moderate the harsh effects of other ingredients.

## Synergistic Combinations

Dang Shen, Bai Shao, Sheng Jiang, Da Zao

## Frequently Asked Questions

### How much gan cao should I take daily?

Typical dosing ranges from 2-15g of dried root daily or 150-300mg of standardized extract. Start with lower doses to assess tolerance, as higher amounts increase risk of mineralocorticoid side effects.

### Can gan cao raise blood pressure?

Yes, gan cao can increase blood pressure through its mineralocorticoid-like effects, causing sodium retention and potassium loss. This risk increases with doses above 50g daily of raw herb or prolonged use.

### Does gan cao interact with blood pressure medications?

Gan cao can reduce effectiveness of ACE inhibitors, diuretics, and other antihypertensive drugs due to its sodium-retaining effects. It may also potentiate digoxin toxicity by causing potassium depletion.

### Is gan cao safe during pregnancy?

Gan cao is not recommended during pregnancy as glycyrrhizin may increase risk of preterm labor and affect fetal development. Studies suggest it can cross the placenta and influence fetal cortisol exposure.

### What's the difference between gan cao and DGL licorice?

DGL (deglycyrrhizinated licorice) has glycyrrhizin removed to prevent blood pressure effects, making it safer for digestive use. Gan cao retains glycyrrhizin, providing adrenal benefits but with higher risk of side effects.

### What clinical research supports gan cao's effect on cortisol and stress?

Multiple clinical studies demonstrate that gan cao's active compounds, particularly glycyrrhizin, can modulate cortisol levels and reduce markers of stress in both animal and human models. Research published in phytotherapy journals shows that regular gan cao supplementation may help normalize HPA axis function, the body's central stress response system. However, most human studies are conducted in Traditional Chinese Medicine contexts, so larger Western clinical trials are still needed to establish definitive efficacy in modern populations.

### Who should avoid gan cao supplementation?

Individuals with hypertension, heart conditions, kidney disease, or a history of hypokalemia (low potassium) should avoid gan cao due to its mineralocorticoid effects, which can elevate blood pressure and deplete potassium over time. People taking diuretics, ACE inhibitors, or other blood pressure medications are at higher risk for adverse interactions. Those with estrogen-sensitive conditions should also consult a healthcare provider, as gan cao may have weak estrogenic activity.

### How does gan cao enhance immune function at the cellular level?

Gan cao stimulates the production of interferon-gamma and enhances natural killer cell activity, both critical components of the innate immune response against viral infections. The ingredient's polysaccharides and glycyrrhizin work synergistically to upregulate immune signaling pathways and increase antibody production. This mechanism explains gan cao's traditional use for upper respiratory support and its emerging role in immune modulation formulas.

### Can Gan Cao (Glycyrrhiza uralensis) help with digestive issues like IBS or gastric irritation?

Gan Cao may support digestive health through glycyrrhetinic acid's ability to stimulate gastric mucus secretion and prostaglandin E2 synthesis, which helps protect the mucosal lining from irritation. While observational studies suggest reduced gastric discomfort, large-scale clinical trials specifically for IBS are lacking, making evidence preliminary. It is often used in Traditional Chinese Medicine formulas for digestive complaints alongside other herbs.

### What are the side effects or risks of taking Gan Cao long-term?

Long-term or high-dose use of Gan Cao can cause pseudohyperaldosteronism due to glycyrrhizin's inhibition of 11β-HSD2, leading to sodium retention, potassium loss, elevated blood pressure, and edema. These effects are dose-dependent and more pronounced with intakes above 100mg glycyrrhizin daily for extended periods. Individuals with hypertension, kidney disease, or those taking corticosteroids or diuretics should exercise particular caution.

### How does Gan Cao support the immune system?

Glycyrrhizin in Gan Cao modulates the NF-κB signaling pathway, promoting interferon-γ production and enhancing antiviral immune responses. In vitro and small human studies have demonstrated 40–60% increases in interferon production, suggesting meaningful immunomodulatory activity. These mechanisms support its traditional use during respiratory infections, though large randomized trials are still needed to confirm clinical efficacy.

### Is Gan Cao the same as DGL licorice, and which form is safer?

Gan Cao (Glycyrrhiza uralensis) is the whole-root herb containing glycyrrhizin, whereas DGL (deglycyrrhizinated licorice) is a processed form with glycyrrhizin removed to reduce hormonal side effects. DGL is generally considered safer for long-term digestive use because it lacks the mineralocorticoid-like activity that can raise blood pressure and disrupt electrolyte balance. Whole Gan Cao is preferred in Traditional Chinese Medicine formulas for its broader systemic effects, but DGL is favored in Western supplementation for gastrointestinal applications.

---

*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
*License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*