DGL for Health & Longevity

Evidence Review created on 06/22/2026 using AI4L / Opus 4.8

Also known as: Deglycyrrhizinated Licorice, Deglycyrrhizinated Liquorice, Deglycyrrhized Liquorice, DGL Licorice

Motivation

DGL is a processed form of licorice root in which most of a compound called glycyrrhizin has been removed. Whole licorice has been used for thousands of years to soothe the stomach, but glycyrrhizin can raise blood pressure and disturb the body’s salt and water balance when taken regularly. Removing it leaves behind the plant’s soothing and protective parts while stripping away the main safety concern. The result is a chewable or powdered supplement taken mainly to calm the digestive tract.

For most of the twentieth century, before modern acid-blocking drugs existed, DGL was studied as a treatment for stomach and small-intestine ulcers, and it remains a popular self-care option for heartburn, indigestion, and recurring mouth ulcers. It is thought to work by helping the lining of the gut produce more of its own protective mucus rather than by blocking acid.

This review examines what the evidence says about DGL’s benefits and risks, the quality of that evidence, how it is typically used, and where the most meaningful uncertainties remain.

Benefits - Risks - Protocol - Conclusion

Grokipedia

Deglycyrrhizinated licorice

This Grokipedia entry provides a general-reference overview of DGL, covering its preparation, proposed digestive uses, and the rationale for removing glycyrrhizin. It is a convenient starting orientation but is not a substitute for the clinical sources cited elsewhere in this review.

Examine

Licorice

This Examine page compiles the human evidence on licorice and its forms, including deglycyrrhizinated licorice, with attention to dosing, effectiveness, and safety. It is a rigorously sourced reference for cross-checking specific claims about DGL.

ConsumerLab

Licorice and DGL Supplements, Candies, and Tea Review

This ConsumerLab review independently tests licorice and DGL supplements, candies, and teas, reporting measured glycyrrhizin content alongside quality and cost comparisons. It is directly useful for confirming that a product labeled deglycyrrhizinated actually has low glycyrrhizin, the central sourcing concern for DGL.

Systematic Reviews

This section summarizes systematic reviews and meta-analyses relevant to DGL and licorice in the digestive and oral-mucosal contexts where DGL is primarily used.

Non-Chinese herbal medicines for functional dyspepsia - Báez et al., 2023

This Cochrane review of 41 trials assessed 27 herbal medicines for functional dyspepsia and found that Glycyrrhiza glabra (licorice) produced a large improvement in symptoms in a single 50-participant trial (moderate-certainty evidence). It is the most authoritative pooled appraisal touching on licorice for upper-gut symptoms.

Effect of polyphenol compounds on Helicobacter pylori eradication: a systematic review with meta-analysis - Wang et al., 2023

This meta-analysis of 12 randomized trials found that polyphenol compounds, including licorice, improved Helicobacter pylori (a stomach bacterium linked to ulcers) eradication rates when added to standard triple therapy, without increasing side effects. It is relevant because anti-H. pylori activity is one proposed contributor to licorice’s ulcer benefits.

Topical Licorice for Aphthous: A Systematic Review of Clinical Trials - Dorsareh et al., 2023

This systematic review of six trials in 314 subjects found that topical licorice significantly reduced pain, ulcer size, and healing time in recurrent aphthous stomatitis (recurring mouth ulcers) without adverse effects. It supports the oral-mucosal use for which DGL is commonly taken as a chewable.

Comparative Efficacy of Therapeutic Interventions for the Management of Recurrent Aphthous Ulcers: A Systematic Review and Network Meta-Analysis - Cheng et al., 2023

This network meta-analysis of 38 trials in 2,773 patients ranked treatments for recurrent mouth ulcers and identified a licorice-containing formulation among the more effective options for reducing ulcer diameter. It places licorice’s oral-ulcer effect in the context of competing therapies.

Mechanism of Action

Mucosal protection over acid suppression: DGL’s proposed central action is enhancing the stomach and intestinal lining’s own defenses rather than reducing acid. It is thought to increase the secretion and quality of protective mucus, prolong the lifespan of surface mucosal cells, and stimulate new cell growth in the gut wall, thereby strengthening the barrier that normally shields tissue from acid and pepsin (a digestive enzyme).
Prostaglandin-related pathway: Several lines of evidence attribute DGL’s protective effect to local increases in prostaglandins (hormone-like lipids that promote mucus and bicarbonate secretion and support mucosal blood flow). This contrasts with NSAIDs (non-steroidal anti-inflammatory drugs such as aspirin), which damage the gut by suppressing the same prostaglandins.
Anti-Helicobacter and anti-inflammatory activity: Licorice flavonoids show activity against Helicobacter pylori, the bacterium responsible for most peptic ulcers, and exert anti-inflammatory and antioxidant effects on inflamed mucosa. These may contribute to ulcer healing and symptom relief, though their relative importance in DGL specifically is uncertain.
Why glycyrrhizin is removed: Whole licorice’s glycyrrhizin is metabolized to glycyrrhetic acid, a potent inhibitor of 11β-HSD2 (11-beta-hydroxysteroid dehydrogenase type 2, an enzyme that protects the mineralocorticoid receptor from cortisol). Inhibiting it produces a state resembling excess aldosterone (the salt-retaining hormone), causing high blood pressure, low potassium, and fluid retention. Deglycyrrhization removes this compound, separating the mucosal benefits from the salt-retention risk.
Competing mechanistic views: Some pharmacological studies (e.g., on rat gastric mucosa) found that DGL had little or no effect on prostaglandin synthesis, challenging the prostaglandin hypothesis and suggesting that direct cytoprotection or other flavonoid actions may dominate. The exact mechanism therefore remains incompletely resolved.
Pharmacological properties: DGL is a multi-component botanical extract rather than a single defined drug, so it has no single half-life, selectivity profile, or clearance pathway; with glycyrrhizin removed, the systemically active glycyrrhetic acid that drives whole-licorice pharmacokinetics is largely absent, and its actions are believed to be predominantly local within the gut lumen and mucosa.

Historical Context & Evolution

Original use: Licorice root has been used for millennia in traditional Chinese, Ayurvedic, Greek, and European medicine as a remedy for cough, sore throat, and digestive complaints, and as a flavoring and sweetening agent. Its use as an antacid and soother for “gastric discomfort and peptic ulcers” predates modern pharmacology.
Path to deglycyrrhization: In the mid-twentieth century, whole licorice and the semi-synthetic derivative carbenoxolone were used for peptic ulcers but caused frequent salt retention, high blood pressure, and low potassium due to glycyrrhizin. Researchers developed deglycyrrhizinated licorice to retain the ulcer-healing effect while eliminating these adverse effects, and standardized preparations on experimental gastric ulcers in animals.
What the early research found: Controlled clinical studies from 1969 to 1982 reported endoscopic healing of gastric and duodenal ulcers with DGL tablets, in some series with healing rates and mucosal normalization comparable to mucosal-protective drugs of the era. Pharmacological work in rats showed DGL protected against aspirin-induced mucosal damage and accelerated renewal of stomach epithelium, and that DGL combined with cimetidine (an early acid-reducing drug) gave greater protection than low doses of either alone.
Evolution of standing: With the arrival of H2 blockers (histamine-blocking acid-reducing drugs), proton pump inhibitors, and H. pylori eradication therapy from the 1980s onward, interest in DGL as a primary ulcer treatment faded, and the older trials are widely viewed as methodologically limited by modern standards. Rather than being formally disproven, DGL was largely displaced by more potent, better-studied drugs; it has persisted in integrative and self-care use for reflux, indigestion, and mouth ulcers, and renewed interest in non-drug mucosal support and in licorice flavonoids keeps the question open as to what role, if any, it holds today.

Expected Benefits

A dedicated search of clinical trials, systematic reviews, and expert sources was performed to compile the benefit profile below before writing this section.

Medium 🟩 🟩

Recurrent Aphthous (Canker) Sore Relief

Licorice applied to or dissolved in the mouth appears to reduce the pain, size, and healing time of recurrent mouth ulcers. A 2023 systematic review of six randomized trials (314 subjects) reported significant benefits with no adverse effects, and a 2023 network meta-analysis of 38 trials ranked a licorice-containing formulation among the more effective options for reducing ulcer diameter. DGL chewable tablets and patches are a common practical vehicle, though most trials tested licorice extracts generally rather than DGL by name, which limits how precisely the effect can be attributed to DGL.

Magnitude: Faster healing (typically within 4–8 days versus longer untreated) with meaningful reductions in pain and ulcer size across trials.

Functional Dyspepsia Symptom Relief

DGL and licorice are taken for indigestion-type symptoms such as upper-abdominal discomfort, fullness, and early satiety. The 2023 Cochrane review of herbal medicines for functional dyspepsia found that Glycyrrhiza glabra produced a large symptom improvement in one 50-participant trial graded as moderate-certainty, placing it among the better-performing single herbs reviewed. The evidence is limited to small numbers of participants and short durations, and trials used various licorice preparations rather than standardized DGL.

Magnitude: Standardized mean difference of about −1.86 (a large effect) in the single trial of Glycyrrhiza glabra in the Cochrane review.

Low 🟩

Peptic Ulcer (Gastric and Duodenal) Healing

The historical clinical case for DGL rests on gastric- and duodenal-ulcer healing. Controlled studies from 1969–1982 reported endoscopic healing of chronic ulcers, and animal work showed protection against aspirin-induced mucosal damage via enhanced mucus, cell turnover, and barrier function. The grade is Low because these trials are old, small, and methodologically weak by modern standards, and DGL has not been re-evaluated against contemporary acid-suppressing and H. pylori-eradication therapy, which is now the standard of care.

Magnitude: Older series reported ulcer healing in a majority of treated patients over several weeks; no reliable modern effect estimate exists.

By strengthening mucosal defenses rather than blocking acid, DGL is proposed to blunt the gastric damage caused by aspirin and similar NSAIDs. This rests mainly on animal experiments showing DGL reduced aspirin-induced mucosal damage and on the prostaglandin-related mechanism, with limited direct human confirmation. It is presented for the proactive, risk-aware reader who may use NSAIDs and is interested in gut-lining support, not as an established preventive.

Magnitude: Not quantified in available studies.

Speculative 🟨

Helicobacter pylori Support Alongside Standard Therapy

Licorice flavonoids show activity against Helicobacter pylori, and a 2023 meta-analysis found polyphenol compounds (including licorice) improved eradication rates when added to standard triple therapy. Whether DGL specifically contributes meaningfully as an add-on, and at what dose, has not been established in dedicated DGL trials; the basis is mechanistic plus indirect pooled data on licorice.

Soothing of Reflux and Heartburn Symptoms

DGL is widely used for reflux and heartburn on the rationale that it supports the esophageal and gastric lining rather than suppressing acid. This use is supported chiefly by mechanistic reasoning and practitioner experience; controlled trials of DGL specifically for gastroesophageal reflux are lacking, so the benefit remains anecdotal and mechanistic.

Benefit-Modifying Factors

Genetic polymorphisms: No genetic variants are established to predict who benefits more from DGL; as a multi-component botanical acting locally in the gut, its efficacy is not known to depend on drug-metabolizing or transporter polymorphisms (e.g., CYP (cytochrome P450, the liver’s main drug-metabolizing enzymes) or ABCB1 (a gene encoding a drug-efflux transporter) variants), so no pharmacogenetic factor reliably modifies the benefit.
Helicobacter pylori status: Whether a person’s ulcer or dyspepsia is driven by Helicobacter pylori infection likely influences response; benefit may be greater when antibacterial flavonoid activity is relevant, and DGL is not a substitute for guideline eradication therapy when infection is present.
Baseline symptom severity and cause: Those with mild, lining-related upper-gut symptoms may notice more benefit than those whose symptoms stem from causes DGL does not address (e.g., motility disorders or non-acid reflux). Baseline ulcer presence (confirmed by endoscopy) was the population in which the historical healing signal was seen.
Concurrent NSAID or irritant exposure: People regularly exposed to aspirin, other NSAIDs, or alcohol may derive more relative benefit from a mucosal-protective agent, since DGL’s proposed action targets exactly this type of injury.
Sex-based differences: No reliable sex-specific efficacy differences for DGL have been established; the historical trials enrolled both sexes without reporting consistent sex effects, so any difference remains unquantified.
Age-related considerations: Older adults, who have higher background rates of ulcers, reflux, and NSAID use, are a plausible group to benefit, but they are also more likely to be on interacting medications and to have conditions requiring formal evaluation rather than self-treatment; benefit should be weighed against the need to rule out serious causes of upper-gut symptoms.

Potential Risks & Side Effects

A dedicated search of drug-reference and clinical sources was performed to compile the side-effect profile below before writing this section.

Low 🟥

Residual Glycyrrhizin and Pseudohyperaldosteronism

Although deglycyrrhization removes most glycyrrhizin, products vary and trace amounts can remain; very high or prolonged intake could still, in principle, contribute to pseudohyperaldosteronism (a salt-retention state that mimics excess of the salt-holding hormone aldosterone) seen with whole licorice. A documented case described a person who developed high blood pressure, low potassium, fainting, and dangerous heart-rhythm disturbances after ingesting large amounts of a product labeled deglycyrrhizinated licorice for years. This underscores that “deglycyrrhizinated” does not guarantee zero glycyrrhizin and that quality and dose matter.

Magnitude: Rare at typical doses; risk rises with large, chronic intake or poorly deglycyrrhized products. True licorice raises systolic blood pressure measurably, whereas properly deglycyrrhized DGL is expected to have a markedly smaller effect.

Mild Gastrointestinal Effects

As an orally taken botanical, DGL can cause minor digestive complaints such as nausea, stomach upset, or changes in bowel habits in some users. These are generally mild and self-limiting. The chewable forms also contain sweeteners and flavorings that some people tolerate poorly.

Magnitude: Not quantified in available studies.

Speculative 🟨

Drug and Hormone Interactions via Licorice Constituents

Licorice constituents can affect potassium balance and may interact with drugs sensitive to potassium levels or with hormone-related pathways; some licorice components show mild estrogen-like activity in laboratory and animal models. With glycyrrhizin largely removed, these concerns are attenuated for DGL, but residual constituents and product variability mean interaction potential cannot be fully dismissed. The basis is mechanistic and from whole-licorice data rather than DGL-specific human trials.

Pregnancy and Sensitive Populations

High licorice intake in pregnancy has been linked in observational research to adverse outcomes, attributed chiefly to glycyrrhizin. Whether well-deglycyrrhized DGL carries any comparable risk is unstudied, so its safety in pregnancy, breastfeeding, and other sensitive states is unknown and rests on extrapolation from whole-licorice data.

Risk-Modifying Factors

Genetic and individual sensitivity: Some individuals are inherently more sensitive to the mineralocorticoid-like effects of licorice constituents, so even small residual glycyrrhizin may matter more for them; people with known sensitivity should be especially cautious about product quality and dose.
Baseline biomarkers: Pre-existing low potassium or borderline high blood pressure raises the consequence of any residual glycyrrhizin effect; baseline blood pressure and potassium help gauge risk.
Sex-based differences: No consistent sex-based difference in DGL adverse effects has been established; the estrogen-like activity of certain licorice components is a theoretical consideration more relevant to whole licorice than to DGL.
Pre-existing conditions: People with high blood pressure, heart failure, kidney disease, low potassium, or heart-rhythm disorders are most vulnerable to any salt-retention effect and should regard chronic or high-dose use with particular caution.
Age-related considerations: Older adults more often have hypertension, take diuretics or other potassium-affecting drugs, and have reduced physiological reserve, which amplifies the consequences of any residual glycyrrhizin effect and warrants closer attention at the older end of the target range.

Key Interactions & Contraindications

Antihypertensive drugs: Any residual glycyrrhizin can oppose blood-pressure-lowering medicines (e.g., ACE inhibitors (angiotensin-converting-enzyme inhibitors, which relax blood vessels) such as lisinopril, ARBs (angiotensin-receptor blockers, which also relax blood vessels) such as losartan, calcium channel blockers such as amlodipine). Severity: caution. Consequence: reduced blood-pressure control. Mitigation: use well-deglycyrrhized products at standard doses and monitor blood pressure.
Diuretics and potassium-depleting drugs: Loop and thiazide diuretics (e.g., furosemide, hydrochlorothiazide) and stimulant laxatives can lower potassium; combined with any residual glycyrrhizin this raises the risk of dangerously low potassium. Severity: caution to avoid with high-dose use. Consequence: hypokalemia (low blood potassium causing weakness and arrhythmia). Mitigation: avoid high-dose or prolonged use; monitor potassium.
Digoxin: Low potassium increases the toxicity of digoxin (a heart medication). Severity: caution. Consequence: digoxin toxicity (nausea, visual changes, dangerous arrhythmias). Mitigation: avoid potassium-lowering combinations; monitor potassium and digoxin levels.
Corticosteroids: Licorice constituents can prolong and intensify corticosteroid (anti-inflammatory steroid) effects by slowing their breakdown. Severity: caution. Consequence: enhanced steroid effect and side effects. Mitigation: separate use and monitor for steroid excess; prefer well-deglycyrrhized products.
Over-the-counter NSAIDs and antacids: DGL is often used alongside NSAIDs (e.g., ibuprofen, aspirin) for gut protection and alongside antacids; no harmful interaction is established, and timing DGL before meals is the usual practical approach. Severity: monitor. Consequence: none well documented.
Supplement interactions and additive effects: Other potassium-affecting or blood-pressure-affecting supplements (e.g., whole licorice extract, high-dose stimulant herbs) can add to any residual glycyrrhizin effect; combining DGL with whole-licorice products is the clearest additive concern. Other mucosal-soothing supplements (e.g., slippery elm, marshmallow root, zinc-carnosine) are commonly combined without documented harm. Severity: caution for whole-licorice stacking. Consequence: additive salt retention.
Populations who should avoid or use only under supervision: Those with uncontrolled hypertension, heart failure (e.g., NYHA (New York Heart Association) Class III–IV, severe symptomatic heart failure), significant kidney disease, low potassium, serious heart-rhythm disorders, and those who are pregnant or breastfeeding should avoid chronic or high-dose use given the residual glycyrrhizin uncertainty.

Risk Mitigation Strategies

Choose genuinely deglycyrrhized products: To mitigate residual-glycyrrhizin pseudohyperaldosteronism, select products specifying low glycyrrhizin content (commonly stated as under 3% or “glycyrrhizin-free”); this directly limits the salt-retention risk that whole licorice carries.
Keep doses standard and time-limited: To mitigate cumulative glycyrrhizin exposure, use typical chewable doses (often 380–400 mg, one to two tablets up to three times daily before meals) and reassess after a few weeks rather than using high doses indefinitely; chronic high intake is the main driver of documented harm.
Monitor blood pressure and potassium with prolonged use: To mitigate high blood pressure and low potassium, those using DGL regularly, especially older adults or those on diuretics, can check blood pressure periodically and have potassium measured if symptoms (weakness, palpitations) arise.
Avoid stacking with whole licorice: To prevent additive salt retention, do not combine DGL with whole-licorice teas, candies, or extracts that retain glycyrrhizin.
Rule out serious causes first: To mitigate the risk of masking a treatable or dangerous condition, persistent or alarm-feature symptoms (unintended weight loss, difficulty swallowing, vomiting blood, black stools, anemia) warrant medical evaluation rather than self-treatment with DGL.

Therapeutic Protocol

Standard chewable regimen: Leading integrative practitioners typically describe DGL as a chewable tablet of roughly 380–400 mg taken before meals, often one to two tablets two to three times daily, on the rationale that mixing with saliva activates its mucosal-soothing action. This reflects the most common practitioner-described approach rather than a regimen validated by modern trials.
Competing approaches: Two main approaches exist without one being the default. The conventional path treats reflux and ulcers with acid suppression (proton pump inhibitors, H2 blockers) and H. pylori eradication; the integrative path uses DGL as a mucosal-support adjunct or alternative for milder symptoms. Each addresses a different target (acid versus mucosal defense), and the choice depends on symptom cause and severity.
Who popularized it: DGL’s use in integrative gut protocols has been promoted by naturopathic and functional-medicine practitioners and by consumer-health publications; the historical clinical groundwork came from mid-twentieth-century British and European ulcer researchers.
Best time of day: DGL is generally taken before meals (commonly 15–20 minutes prior) and is sometimes added at bedtime for nighttime symptoms, aligning dosing with periods of symptom provocation.
Half-life: As a multi-component botanical acting largely within the gut, DGL has no single defined half-life; with glycyrrhizin removed, the long-acting systemic constituent of whole licorice is largely absent, and effects are believed to be local and relatively short-lived, supporting repeated dosing around meals.
Single versus split dosing: Split dosing before each main meal (and optionally at bedtime) is the typical pattern rather than a single daily dose, matching the local, meal-related rationale for its action.
Genetic considerations: No pharmacogenetic markers reliably guide DGL dosing; individual sensitivity to residual licorice constituents (mineralocorticoid-like effects) is the main person-level variable and is not predicted by a defined gene test.
Sex-based differences: No established sex-based differences in DGL dosing or response exist; trials have not reported consistent differences.
Age-related considerations: Older adults may warrant more conservative dosing and closer blood-pressure and potassium attention, given more frequent comorbidities and interacting medications.
Baseline biomarkers: Baseline blood pressure and potassium are reasonable to note before regular use, since they frame the residual-glycyrrhizin risk; no efficacy biomarker guides DGL dosing.
Pre-existing conditions: Those with hypertension, heart failure, kidney disease, or low potassium should use the lowest effective dose for the shortest period, or avoid chronic use, given the salt-retention uncertainty.

Discontinuation & Cycling

Lifelong versus short-term: DGL is generally used short-term and symptomatically (for an ulcer-healing course or for episodic reflux, indigestion, or mouth ulcers) rather than as a lifelong daily supplement, in keeping with its symptom-targeted rationale and the lack of long-term safety data.
Withdrawal effects: No specific withdrawal syndrome is described for DGL; stopping it is expected mainly to allow symptoms to return if the underlying cause persists.
Tapering: No tapering protocol is required for DGL; it can generally be stopped directly. Whole licorice, by contrast, may warrant more caution after heavy chronic use because of its glycyrrhizin effects.
Cycling: Cycling is not established as necessary for maintaining efficacy; the practical pattern is use-as-needed during symptomatic periods with breaks when symptoms resolve, which also limits cumulative residual-glycyrrhizin exposure.

Sourcing and Quality

Confirm deglycyrrhization: Look for products that state a low glycyrrhizin content (commonly under 3%) or label themselves glycyrrhizin-free, since “DGL” labeling alone does not guarantee how thoroughly glycyrrhizin was removed and residual amounts drive the main safety concern.
Third-party testing: Prefer products carrying independent quality verification (e.g., NSF, USP, or equivalent third-party testing) to confirm identity, label accuracy, and absence of contaminants, as supplement quality varies widely and some marketed licorice health foods have shown inconsistent component levels.
Form and excipients: Chewable tablets are the most studied practical form for upper-gut and oral use; check the sweeteners, flavorings, and fillers, which differ between brands and can affect tolerability.
Reputable suppliers: Established supplement brands and reputable pharmacies that publish certificates of analysis are preferable; the historical clinical preparations were standardized extracts, and standardization remains a useful marker of quality.

Practical Considerations

Time to effect: Symptomatic soothing of reflux, indigestion, or mouth-ulcer pain may be noticed within days; the historical ulcer-healing data involved several weeks of use, so structural healing, if it occurs, is not immediate.
Common pitfalls: Frequent mistakes include confusing DGL with whole licorice or licorice candy (which retain glycyrrhizin and can raise blood pressure), swallowing rather than chewing chewable forms, using high doses indefinitely, and relying on DGL for alarm-feature symptoms that need medical evaluation.
Regulatory status: In the United States, DGL is sold as a dietary supplement, not an approved drug; it is not FDA-approved for treating ulcers or reflux, and licorice is recognized as a food additive in limited concentrations with warnings about excess intake.
Cost and accessibility: DGL is inexpensive, widely available over the counter, and easy to access; cost is not a meaningful barrier.

Interaction with Foundational Habits

Sleep: Indirect interaction. By easing nighttime reflux and indigestion for some users, DGL taken before bed may improve sleep continuity; there is no evidence it directly alters sleep architecture, and any benefit is secondary to symptom relief.
Nutrition: Direct, meal-linked interaction. DGL is taken before meals so it can coat and soothe the gut lining as food and acid arrive; it pairs naturally with reflux-friendly eating patterns (smaller meals, limiting alcohol and trigger foods). It should not be combined with whole-licorice foods or teas, which reintroduce glycyrrhizin.
Exercise: No meaningful direct interaction. DGL is not known to blunt or enhance training adaptations; for the proactive reader who uses NSAIDs around heavy training, its proposed gut-lining support is the only plausible, and unproven, point of contact.
Stress management: Indirect interaction. Because stress aggravates reflux and dyspepsia and may affect ulcer healing, stress-reduction practices can complement DGL’s mucosal-support role; DGL itself is not established to affect cortisol or the stress response once glycyrrhizin is removed.

Monitoring Protocol & Defining Success

Baseline assessment is worthwhile mainly to frame the residual-glycyrrhizin safety question and to characterize the symptoms being treated before starting regular DGL use.

Ongoing monitoring is light for short-term use; for prolonged or higher-dose use, blood pressure and potassium can be checked periodically (for example, at baseline, then every 3–6 months, or sooner if symptoms of salt retention appear).

Biomarker	Optimal Functional Range	Why Measure It?	Context/Notes
Blood pressure	~110–125 / 70–80 mmHg	Detects salt-retention effect from any residual glycyrrhizin	Check at baseline and periodically with regular use; more important in older adults and those on diuretics
Serum potassium	4.0–4.5 mmol/L	Low potassium (hypokalemia) is the hallmark of glycyrrhizin excess	Conventional reference range (3.5–5.0 mmol/L) is wider; functional target favors the mid-upper range; check if symptoms arise
Helicobacter pylori status	Negative	Identifies infection that needs guideline eradication, not self-treatment	Stool antigen or breath test; best done off acid suppressants per testing guidance
Symptom score (reflux/dyspepsia)	Marked reduction from baseline	Defines whether DGL is actually helping	Track via a simple symptom diary; reassess after a few weeks

Qualitative markers help define success beyond labs:

Reduction in heartburn, regurgitation, or upper-abdominal discomfort frequency and intensity
Faster healing and less pain from recurrent mouth ulcers
Improved comfort after meals and fewer nighttime symptoms
Absence of new symptoms suggesting salt retention (unusual weakness, swelling, palpitations)

Emerging Research

Fermented DGL for diabetic nerve damage: A completed phase 2 randomized, double-blind, placebo-controlled trial NCT07148804 (83 participants) tested a fermented deglycyrrhizinated licorice extract providing an amylase enzyme for early diabetic polyneuropathy (nerve damage from diabetes), reporting improved nerve conduction; this extends DGL research beyond the gut, though it uses a specialized fermented preparation. Results were published as Massoud et al., 2026.
Licorice plus low-dose amoxicillin for H. pylori: A planned trial NCT06881524 (374 participants) will test licorice and lotus root powder combined with low-dose amoxicillin against high-dose amoxicillin for Helicobacter pylori eradication; if positive, it would strengthen the case that licorice constituents meaningfully support ulcer-related infection treatment.
Licorice mucoadhesive films for oral lesions: A completed phase 1/2 trial NCT02075749 (60 participants) compared licorice mucoadhesive films with a topical steroid for mouth lesions, addressing pain outcomes relevant to DGL’s oral-ulcer use and to delivery-format innovation.
Future direction — modern reflux and ulcer trials: The clearest gap is the absence of contemporary, well-powered randomized trials of standardized DGL for reflux and peptic ulcer using endoscopic and validated symptom endpoints; such studies could either confirm or weaken the historical signal summarized in Báez et al., 2023.
Future direction — flavonoid mechanism and H. pylori: Research clarifying which licorice flavonoids drive mucosal protection and anti-Helicobacter pylori activity, building on the pooled signal in Wang et al., 2023, could redefine DGL’s role as either a useful adjunct or an inferior option versus standard care.

Conclusion

DGL is a processed licorice extract, taken mostly as a chewable, in which the blood-pressure-raising compound glycyrrhizin has been largely removed, leaving the soothing parts of the root. It is used chiefly to calm the digestive tract, with the best current support for easing recurring mouth ulcers and indigestion-type symptoms, weaker and largely historical support for healing stomach and small-intestine ulcers, and mostly mechanism-based reasoning behind its popular use for heartburn. Its proposed action is to strengthen the gut’s own protective lining rather than to block acid.

The evidence base is uneven. The clinical trials behind its reputation are old and small, and most pooled analyses studied licorice in general rather than DGL by name. Safety is its relative strength: removing glycyrrhizin removes the main risk of whole licorice, though poorly processed products or very high, long-term intake can still cause salt retention, low potassium, and raised blood pressure. Overall, DGL emerges as a low-cost, generally well-tolerated option with reasonable support for easing mouth ulcers and mild indigestion, while its value for healing stomach ulcers and relieving heartburn rests largely on older or mechanism-based evidence.

Top - Benefits - Risks - Protocol

DGL for Health & Longevity

Motivation

Recommended Reading

Grokipedia

Examine

ConsumerLab

Systematic Reviews

Mechanism of Action

Historical Context & Evolution

Expected Benefits

Medium 🟩 🟩

Recurrent Aphthous (Canker) Sore Relief

Functional Dyspepsia Symptom Relief

Low 🟩

Peptic Ulcer (Gastric and Duodenal) Healing

Protection Against NSAID-Related Gastric Irritation

Speculative 🟨

Helicobacter pylori Support Alongside Standard Therapy

Soothing of Reflux and Heartburn Symptoms

Benefit-Modifying Factors

Potential Risks & Side Effects

Low 🟥

Residual Glycyrrhizin and Pseudohyperaldosteronism

Mild Gastrointestinal Effects

Speculative 🟨

Drug and Hormone Interactions via Licorice Constituents

Pregnancy and Sensitive Populations

Risk-Modifying Factors

Key Interactions & Contraindications

Risk Mitigation Strategies

Therapeutic Protocol

Discontinuation & Cycling

Sourcing and Quality

Practical Considerations

Interaction with Foundational Habits

Monitoring Protocol & Defining Success

Emerging Research

Conclusion