Licorice Root for Weight Management: Does It Work?
Licorice root (Glycyrrhiza glabra or Glycyrrhiza uralensis) has a long history in both traditional medicine and food flavouring. In the context of weight management, it is sometimes promoted on the basis of its effects on cortisol metabolism and fat distribution. The honest assessment is more nuanced: there are plausible mechanisms, but the evidence for meaningful weight loss in humans is thin.
Proposed Mechanism
The primary active compounds in licorice root are glycyrrhizin and its metabolite glycyrrhizinic acid (also called glycyrrhizinic acid or 18beta-glycyrrhizinic acid). These compounds inhibit 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), an enzyme that converts inactive cortisone to active cortisol in tissues such as fat.
Elevated local cortisol activity in adipose tissue is associated with visceral fat accumulation. The hypothesis is that by reducing local cortisol activity, licorice-derived compounds might reduce visceral adiposity. This mechanism is biologically coherent — 11beta-HSD1 inhibition is also a pharmaceutical target for obesity and metabolic syndrome research.
Licorice flavonoids (particularly isoliquiritigenin and liquiritigenin) have also been studied for possible effects on adipogenesis — the formation of new fat cells — in laboratory settings, where they showed inhibitory effects in cell culture models.
An Honest Look at the Evidence
Human clinical evidence for licorice root as a weight management aid is limited. A small randomised crossover study by Armanini et al. (2003) found that a licorice flavonoid preparation was associated with a reduction in body fat mass over eight weeks compared to control, though the effect was modest and the study small (Armanini et al., 2003). A follow-up study from the same group (Armanini et al., 2004) examined a topical licorice preparation for reducing thigh fat, which is an unusual application and not generalisable.
A separate trial examining a licorice extract product found reductions in body fat percentage over several weeks, but this was a proprietary product and the study design limited the ability to isolate licorice as the active ingredient.
Overall, the evidence falls into the category of: plausible mechanism, very early-stage human data, small studies with limitations. No high-quality large-scale RCT has established licorice root as an effective weight management intervention.
Effect Sizes (If Any)
In the studies that did show effects, changes in body fat percentage were in the range of a few percentage points over several weeks. These are not clinically impressive reductions, and it is impossible to attribute them confidently to licorice root in isolation without larger, better-controlled studies.
Realistic Expectations
Licorice root is not a fat burner in any meaningful sense. The proposed 11beta-HSD1 inhibition mechanism is pharmacologically interesting but has not translated into clinically meaningful weight loss outcomes in human trials. If you are looking to manage weight, the evidence base strongly favours: consistent caloric deficit, adequate protein intake, resistance training, and sleep quality — none of which licorice root can substitute for.
OstroVit Licorice VEGE 90caps, available at maxfit.ee under the lagritsajuur category, is primarily used for digestive support rather than weight management, which is actually the area where licorice has somewhat stronger evidence.
Better Levers for Weight Management
If weight management is the goal, the interventions with substantially more evidence include:
- Protein-rich diet (protein has the highest satiety and thermic effect of food)
- Resistance training (preserves and builds muscle mass, elevating resting metabolic rate)
- Adequate sleep (sleep deprivation disrupts appetite-regulating hormones)
- Dietary fibre (improves satiety and supports gut health)
Supplements like L-carnitine, green tea extract, and caffeine have more direct (though still modest) evidence for supporting fat metabolism than licorice root.
FAQ
Is licorice root safe for regular use?
This depends critically on whether the product contains glycyrrhizin or is a deglycyrrhizinated licorice (DGL) form. Glycyrrhizin at high doses can cause pseudohyperaldosteronism — elevated blood pressure, water retention, and low potassium — because it also inhibits the enzyme that normally breaks down cortisol in the kidneys. Long-term, high-dose use of glycyrrhizin-containing products is not safe. DGL forms have had this compound removed and are generally considered safer.
Can licorice root reduce belly fat specifically?
The 11beta-HSD1 inhibition mechanism is theoretically more relevant to visceral fat. However, the human evidence is too limited to support claims of targeted visceral fat reduction.
What is licorice root actually evidence-backed for?
Licorice root has the most evidence for soothing gastrointestinal issues — particularly functional dyspepsia and as a mucosal protective agent. This is separate from and not related to weight management claims.
References
Armanini, D., Nacamulli, D., Francini-Pesenti, F., Battagin, G., Ragazzi, E., & Fiore, C. (2003). Glycyrrhetinic acid, the active principle of licorice, can reduce the thickness of subcutaneous thigh fat through topical application. Steroids, 68(10-13), 861-864.
Armanini, D., De Palo, C. B., Mattarello, M. J., Spinella, P., Zaccaria, M., Ermolao, A., ... & Fiore, C. (2004). Effect of licorice on the reduction of body fat mass in healthy subjects. Journal of Endocrinological Investigation, 26(7), 646-650.
Asl, M. N., & Hosseinzadeh, H. (2008). Review of pharmacological effects of Glycyrrhiza sp. and its bioactive compounds. Phytotherapy Research, 22(6), 709-724. https://pubmed.ncbi.nlm.nih.gov/18446848/
