Licorice (Glycyrrhizin excess)

What is Licorice (Glycyrrhizin excess)?

Licorice (Glycyrrhiza glabra) is a perennial herb whose root has been used medicinally for thousands of years. The term “glycyrrhizin excess” refers to licorice preparations that contain high levels of glycyrrhizin, the compound responsible for licorice’s characteristic sweet taste and many of its biological effects. Glycyrrhizin can comprise 2-9% of the licorice root by weight and is approximately 50 times sweeter than sugar.

While licorice root offers potential therapeutic benefits, excessive glycyrrhizin intake can cause serious health complications, leading to a condition called pseudohyperaldosteronism. This has prompted the development of deglycyrrhizinated licorice (DGL) for safer supplementation, though some products intentionally retain high glycyrrhizin content for specific therapeutic applications under medical supervision.

Health benefits & uses

Digestive health (Moderate evidence): Licorice has traditionally been used to treat peptic ulcers and gastritis. Some studies suggest glycyrrhizin may help protect the gastric mucosa and reduce inflammation in the digestive tract.

Respiratory conditions (Limited evidence): Traditional use includes treating coughs, bronchitis, and sore throats. The anti-inflammatory properties of glycyrrhizin may provide some benefit for upper respiratory symptoms, though more research is needed.

Skin conditions (Limited evidence): Topical applications containing glycyrrhizin have been studied for eczema and other inflammatory skin conditions, with some promising but preliminary results.

Hepatic support (Limited evidence): Some research has investigated glycyrrhizin’s potential hepatoprotective effects, particularly in chronic hepatitis, but evidence remains inconclusive and safety concerns limit its use.

How it works

Glycyrrhizin exerts its effects primarily through inhibition of 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), an enzyme that normally converts cortisol to cortisone. When this enzyme is inhibited, cortisol levels remain elevated and can activate mineralocorticoid receptors, leading to sodium retention, potassium loss, and increased blood pressure.

The compound also demonstrates anti-inflammatory effects by modulating various inflammatory pathways and cytokine production. Additionally, glycyrrhizin may have antimicrobial properties and can influence prostaglandin synthesis, which may contribute to its traditional use in digestive disorders.

Dosage

Due to safety concerns, there is no established recommended daily allowance (RDA) or safe upper limit (UL) for glycyrrhizin. Most health authorities recommend limiting glycyrrhizin intake to no more than 100mg per day for short periods (typically 2-4 weeks maximum).

For therapeutic applications, dosing must be carefully monitored by healthcare providers. Some clinical studies have used doses ranging from 150-300mg of glycyrrhizin daily, but only under strict medical supervision with regular monitoring of blood pressure and electrolyte levels.

Consumer products containing licorice often use DGL (deglycyrrhizinated licorice) to minimize glycyrrhizin content while retaining other potentially beneficial compounds. Always consult with a healthcare provider before using high-glycyrrhizin licorice products.

Food sources

Glycyrrhizin is naturally found in:

• Licorice root (Glycyrrhiza glabra) – highest concentration
• Licorice candy made with real licorice extract
• Traditional herbal teas containing licorice root
• Some traditional Chinese medicine preparations
• Certain European herbal remedies

Note that many commercial “licorice” candies in the United States are actually flavored with anise oil rather than real licorice extract, so they contain no glycyrrhizin. Always check product labels to determine actual licorice content.

Safety & side effects

Excessive glycyrrhizin intake can cause serious adverse effects, including:

• High blood pressure (hypertension)
• Low potassium levels (hypokalemia)
• Fluid retention and edema
• Muscle weakness
• Heart rhythm abnormalities
• Headaches
• Fatigue and lethargy

These effects can occur with regular consumption of as little as 50-100mg of glycyrrhizin daily over several weeks. Symptoms typically resolve when licorice consumption is discontinued, but severe cases may require medical intervention.

Interactions

Medications: Glycyrrhizin can interact with numerous drugs, including diuretics, ACE inhibitors, blood pressure medications, and heart medications. It may enhance potassium loss when combined with certain diuretics.

Supplements: May interact with other herbs or supplements that affect blood pressure or electrolyte balance. Avoid combining with other potassium-depleting substances.

Medical conditions: Can exacerbate hypertension, heart conditions, kidney disease, and liver disorders.

Who should be cautious

The following groups should avoid high-glycyrrhizin licorice products:

• Pregnant and breastfeeding women
• People with high blood pressure
• Individuals with heart conditions
• Those with kidney or liver disease
• People taking blood pressure medications
• Individuals with electrolyte imbalances
• Those with a history of stroke

Frequently asked questions

Is DGL (deglycyrrhizinated licorice) safer than regular licorice?

Yes, DGL has had most glycyrrhizin removed, significantly reducing the risk of side effects while potentially retaining other beneficial compounds from licorice root. DGL is generally considered safer for long-term use.

How much licorice candy can I safely eat?

This depends on whether the candy contains real licorice extract. If it does, limit consumption to avoid exceeding 100mg of glycyrrhizin daily. Even small amounts of genuine licorice candy can contribute significant glycyrrhizin intake.

Can licorice help with acid reflux?

Some people use DGL for digestive issues including acid reflux, and there is limited evidence supporting its traditional use. However, high-glycyrrhizin licorice should be avoided due to safety concerns.

How long does it take for licorice side effects to appear?

Side effects from excessive glycyrrhizin can develop within days to weeks of regular consumption, depending on the amount consumed and individual sensitivity. Effects typically resolve within days to weeks after discontinuation.

Is licorice root tea safe to drink daily?

Regular consumption of licorice root tea can lead to glycyrrhizin excess over time. Occasional use is generally safe for most people, but daily consumption should be avoided unless under medical supervision.