Deglycyrrhizinated licorice (DGL), the form of licorice with the compound linked to blood pressure and potassium concerns removed, has some of the more direct placebo-controlled trial evidence among natural heartburn remedies, with symptom improvement documented within the first two weeks of use. Meal timing and specific lifestyle changes remain foundational alongside any supplement approach.
Quick Facts
- DGL licorice: Improved heartburn and regurgitation by day 14 in a double-blind, placebo-controlled trial
- Melatonin: May support lower esophageal sphincter function, smaller trial base
- Avoid peppermint: Can relax the lower esophageal sphincter and worsen reflux
- Meal timing: Eating 3+ hours before lying down reduces nighttime reflux
- Weight management: One of the most consistently evidence-supported reflux interventions
DGL Licorice: The Standout Trial Data
A phase III, double-blind, randomized, placebo-controlled trial of a standardized DGL extract found clinically significant improvement in reflux symptoms, particularly heartburn and regurgitation, beginning in the second week of treatment, with the treatment group showing better and earlier symptom resolution than placebo across a validated GERD quality-of-life questionnaire. The proposed mechanism is that DGL promotes protective mucus production in the stomach and esophagus lining, rather than directly neutralizing acid the way antacids do.
Melatonin and What to Avoid
Melatonin, beyond its sleep role, is also produced in the gastrointestinal tract and has been studied in smaller trials for supporting lower esophageal sphincter tone, though the trial base is considerably smaller than for DGL. Notably, peppermint, often recommended for general digestive complaints, can relax the lower esophageal sphincter and worsen heartburn specifically, making it one supplement that's better suited to bloating than reflux. See our full Melatonin guide.
What the Research Actually Shows
DGL licorice for reflux symptom improvement. Evidence level: Promising. Positive placebo-controlled trial data, though more independent trials would strengthen confidence.
Melatonin for reflux. Evidence level: Emerging. Smaller trial base than DGL.
Weight loss for reflux reduction. Evidence level: Established. Well-documented relationship between excess weight and reflux severity.
Lifestyle Factors That Matter
Avoiding meals within three hours of lying down, elevating the head of the bed, reducing alcohol and late-night eating, and managing body weight are all well-supported, foundational approaches that work alongside, not instead of, any supplement.
Safety & Who Should Be Cautious
Regular (non-deglycyrrhizinated) licorice can raise blood pressure and lower potassium with prolonged use, which is why DGL specifically, with that compound removed, is the appropriate form for this purpose. The FDA doesn't tightly regulate licorice supplements, so product quality and standardization vary considerably between brands. Persistent reflux despite lifestyle changes and supplements warrants medical evaluation, since chronic untreated GERD carries risks including esophageal damage.
ⓘ DGL licorice has some of the more direct placebo-controlled trial evidence among natural heartburn remedies, with improvement documented within two weeks. Make sure any product is specifically labeled deglycyrrhizinated, as regular licorice carries blood pressure risks.
Frequently Asked Questions
Does DGL licorice actually work for heartburn?
A placebo-controlled trial found clinically significant improvement in heartburn and regurgitation starting in the second week of use, one of the more direct pieces of trial evidence among natural reflux remedies.
Is regular licorice the same as DGL?
No, DGL has glycyrrhizin, the compound linked to blood pressure elevation and potassium loss, removed, making it the safer form for regular use.
Why should I avoid peppermint for heartburn?
Peppermint can relax the lower esophageal sphincter, the muscle that keeps stomach acid from moving upward, potentially worsening reflux symptoms.
What lifestyle changes help most with acid reflux?
Avoiding meals close to bedtime, elevating the head of the bed, and managing body weight are among the most consistently evidence-supported changes.
Scientific References
- Raveendra, K. R., Jayachandra, Sushma, K. V., et al. "Efficacy and Safety of GutGard in Managing Gastroesophageal Reflux-Related Symptoms: A Phase III, Single-Centre, Double-Blind, Randomized Placebo-Controlled Trial." Evidence-Based Complementary and Alternative Medicine, 2025.
- Jehangir, A., Parkman, H. P. "Role of Melatonin and Other Alternative and Complementary Agents in Gastroesophageal Reflux Disease and Peptic Ulcer Disease." Frontiers in Bioscience, 2018;10:349-372.
Disclaimer
This article is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. It does not constitute medical advice. Persistent or severe reflux symptoms should be evaluated by a qualified healthcare provider, and those with hypertension should discuss licorice-containing supplements with their doctor.
