What the evidence says. Graded moderate: several short, single-centre RCTs of one standardized extract (GutGard) show real symptom relief in dyspepsia and reflux, but nearly all are small and manufacturer-funded, and a 2025 meta-analysis found licorice's effect on actual ulcer healing was not statistically significant. (Moderate evidence: Several controlled trials; effects real but modest or context-dependent.)
What is DGL (Deglycyrrhizinated Licorice)?
DGL (Deglycyrrhizinated Licorice) (Glycyrrhiza glabra) is a gut and immune supplement used for ease functional dyspepsia. NutriDex grades the human evidence as Moderate. DGL is licorice root processed to strip out glycyrrhizin, the compound that raises blood pressure and depletes potassium, leaving the flavonoids thought to soothe the gut. The best evidence is for functional dyspepsia and reflux: in placebo-controlled trials of a standardized extract (GutGard, 150 mg/day), total symptom and Nepean dyspepsia scores fell significantly over 30 days, and reflux-related heartburn and regurgitation improved over 28 days. A small randomized trial suggested it lowered H. pylori load, and old uncontrolled work found DGL mouthwash sped canker-sore healing. However, most trials enrolled only 50–200 people, ran at one site, and were funded by the extract's maker; a 2025 systematic review of 9 trials (618 people) found licorice improved ulcer-healing and pain numerically but not significantly. So DGL is plausibly helpful for indigestion comfort, but the proof is thin and likely overstated by industry sponsorship.
Purported Benefits
✓Ease functional dyspepsia
✓Soothe heartburn & reflux symptoms
✓Speed canker-sore healing
✓Protect gastric lining from aspirin
Evidence by outcome
The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.
Standardized flavonoid extract (e.g. GutGard) 75 mg twice daily, or 380–760 mg chewable DGL before meals; glycyrrhizin should be <3%.
Active Compounds
Glabridin & licorice flavonoidsLiquiritin / isoliquiritinGlycyrrhizin (removed to <3%)
Safety & Cautions
⚠
True DGL (glycyrrhizin <3%) is well tolerated; unlike whole licorice it should not cause the high blood pressure, low potassium, fluid retention or pseudo-aldosteronism seen with glycyrrhizin. Mild GI upset is the main complaint. Risk rises if a product is mislabelled or you take ordinary (non-DGL) licorice: that can interact dangerously with antihypertensives, diuretics, digoxin, corticosteroids and warfarin, and worsen heart, kidney or liver disease and low potassium. Pregnant people should avoid high licorice intake; check that any product is genuinely deglycyrrhizinated. Educational only — always check with your doctor or pharmacist before combining DGL (Deglycyrrhizinated Licorice) with any medicine.
Common questions about DGL (Deglycyrrhizinated Licorice)
What is DGL (Deglycyrrhizinated Licorice) used for?
DGL (Deglycyrrhizinated Licorice) is most often taken for Ease functional dyspepsia, Soothe heartburn & reflux symptoms, Speed canker-sore healing, Protect gastric lining from aspirin. Licorice with the blood-pressure-raising glycyrrhizin removed, for stomach comfort.
Does DGL (Deglycyrrhizinated Licorice) work — what does the evidence say?
Moderate evidence. Several controlled trials; effects real but modest or context-dependent. DGL is licorice root processed to strip out glycyrrhizin, the compound that raises blood pressure and depletes potassium, leaving the flavonoids thought to soothe the gut. The best evidence is for functional dyspepsia and reflux: in placebo-controlled trials of a standardized extract (GutGard, 150 mg/day), total symptom and Nepean dyspepsia scores fell significantly over 30 days, and reflux-related heartburn and regurgitation improved over 28 days. A small randomized trial suggested it lowered H. pylori load, and old uncontrolled work found DGL mouthwash sped canker-sore healing. However, most trials enrolled only 50–200 people, ran at one site, and were funded by the extract's maker; a 2025 systematic review of 9 trials (618 people) found licorice improved ulcer-healing and pain numerically but not significantly. So DGL is plausibly helpful for indigestion comfort, but the proof is thin and likely overstated by industry sponsorship.
What is the typical dose of DGL (Deglycyrrhizinated Licorice)?
Standardized flavonoid extract (e.g. GutGard) 75 mg twice daily, or 380–760 mg chewable DGL before meals; glycyrrhizin should be <3%.
Is DGL (Deglycyrrhizinated Licorice) safe? Any cautions or side effects?
True DGL (glycyrrhizin <3%) is well tolerated; unlike whole licorice it should not cause the high blood pressure, low potassium, fluid retention or pseudo-aldosteronism seen with glycyrrhizin. Mild GI upset is the main complaint. Risk rises if a product is mislabelled or you take ordinary (non-DGL) licorice: that can interact dangerously with antihypertensives, diuretics, digoxin, corticosteroids and warfarin, and worsen heart, kidney or liver disease and low potassium. Pregnant people should avoid high licorice intake; check that any product is genuinely deglycyrrhizinated.
How many studies support DGL (Deglycyrrhizinated Licorice)?
NutriDex cites 9 sources for DGL (Deglycyrrhizinated Licorice), graded "Moderate".
Cite this page
APA
Peh, D. (2026). DGL (Deglycyrrhizinated Licorice) (Glycyrrhiza glabra): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 16 Sept 2026, from https://nutridex.info/s/dgl-licorice
BibTeX
@misc{nutridex_dgl_licorice,
author = {Peh, Daryl},
title = {DGL (Deglycyrrhizinated Licorice) (Glycyrrhiza glabra): Benefits, Dosage, Side Effects \& Evidence},
year = {2026},
howpublished = {NutriDex --- The Supplement Research Compendium},
url = {https://nutridex.info/s/dgl-licorice},
note = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-09-16}
}
For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.