Licorice Root —
five actives wearing the same name.
“Licorice extract” on an ingredient list tells you almost nothing. We broke down the five distinct compounds hiding behind one marketing term — and which of them the clinical evidence actually supports.
K Brand Ingredient Proof Rating
Licorice Root Extract
Glycyrrhiza spp. · Botanical active family · 5 distinct constituents
What licorice actually is — and why the label is misleading
When a K-beauty product boasts “licorice root extract,” the ingredient you’re buying could be one of at least five chemically distinct compounds — each with its own mechanism, its own evidence base, and its own reasonable-or-not marketing claim. Most consumers, and plenty of formulators, treat them as interchangeable. They aren’t.
The five constituents worth knowing are glabridin, licochalcone A, glycyrrhizin, glycyrrhetinic acid (enoxolone), and liquiritin. They come from different species within the Glycyrrhiza genus, target different pathways in skin, and have wildly different amounts of clinical data behind them. Collapsing all of that into a single INCI line is how the hype gets ahead of the science.
The honest summary: licorice is genuinely one of the most studied botanical families in dermatology — but “most studied” is relative. Most of the work is preclinical, most of the clinical studies are small (under 100 participants), and the two hero marketing claims — glabridin as a hydroquinone alternative, licochalcone A for rosacea — are the least independently validated of the lot.
“No published RCT has evaluated isolated topical glabridin monotherapy for melasma or post-inflammatory hyperpigmentation. All available human data come from multi-ingredient formulations where glabridin’s specific contribution cannot be isolated.”
Clinical evidence review of licorice-derived actives · Journal of Cosmetic Dermatology, 2024
The five constituents — what each one actually does
Here’s the honest breakdown of the licorice family, scored on independent clinical evidence — not preclinical mechanism or marketing prominence. The gap between those two measures is where this ingredient’s reputation gets oversold.
Glabridin
Glycyrrhiza glabra
Tyrosinase inhibitor · Depigmenting
Licochalcone A
Glycyrrhiza inflata
Anti-inflammatory · Soothing
Liquiritin
Glycyrrhiza glabra
Depigmenting flavonoid
Glycyrrhetinic Acid
Enoxolone · from glycyrrhizin
Cortisol potentiator · Anti-inflammatory
Glycyrrhizin
Glycyrrhiza glabra
Mild anti-inflammatory · Precursor
Licorice vs. what it’s actually competing with
The implicit sell for most licorice-forward products is that it’s a “natural alternative” to harsher depigmenting agents. The systematic review data doesn’t support that framing. Across pooled evidence, licorice-derived treatments consistently test as better than placebo but less effective than hydroquinone for hyperpigmentation. Full stop.
⚠ Where the “16× more potent than hydroquinone” claim comes from
The number originates from a 1998 in-vitro study by Yokota et al. comparing glabridin to kojic acid — not hydroquinone — in melanoma cells. The comparison has been misquoted in marketing for decades. No head-to-head clinical trial of isolated glabridin against hydroquinone has ever been published in a peer-reviewed dermatology journal.
Direct comparisons with newer generation depigmenting agents — tranexamic acid, thiamidol, cysteamine — are also missing from the licorice literature. If a product is marketed as a “gentler alternative” to these, it’s a vibes argument, not a data one. The ingredient family’s strongest credible positioning is as a combination partner — pairing well with ascorbic acid, niacinamide, and sunscreen rather than standing alone.
Evidence by claim — what actually holds up
| Benefit Claimed | Evidence | What the studies actually found |
|---|---|---|
| Brightens dark spots & melasma | Moderate | Real but modest. Liquiritin has split-face vehicle-controlled data (n=20) and a larger comparative RCT (n=90). Glabridin has none. Whole-extract nanoparticle trial (n= small) showed significant MMASI improvement over 12 weeks. Less effective than hydroquinone overall. |
| Calms atopic dermatitis & eczema | Moderate | Two pediatric RCTs showed licochalcone A matched 1% hydrocortisone on SCORAD over 4–6 weeks. Atopiclair (glycyrrhetinic acid complex) has a Cochrane-reviewed evidence base for pediatric AD. Credible as non-steroidal adjunct in mild disease. |
| Reduces redness & rosacea | Limited | All rosacea data for licochalcone A is Beiersdorf-sponsored, open-label, and lacks active comparators (like metronidazole or azelaic acid). Compatible with an anti-inflammatory effect, insufficient to define the role. Don’t buy licorice products expecting metronidazole-level results. |
| Anti-aging & wrinkle reduction | Limited | Almost entirely preclinical. Glabridin shows antioxidant and phytoestrogen activity in cell culture, but no clinical wrinkle-endpoint studies on isolated licorice constituents. When you see “anti-aging licorice” marketing, it’s mechanism-based speculation, not trial data. |
| Post-inflammatory hyperpigmentation (PIH) | Limited | Extrapolated from melasma data rather than directly studied. Plausible benefit — same tyrosinase and melanosome pathways — but no PIH-specific RCTs exist for any single licorice constituent. Combination formulas with niacinamide or vitamin C are the defensible choice here. |
| Natural alternative to hydroquinone | None | Marketing language with no clinical support. Systematic reviews consistently find licorice less effective than hydroquinone. The “natural alternative” framing conflates safety (genuinely good) with efficacy (modest). Different things. |
Safety, sourcing, and regulatory reality
On safety, licorice earns unqualified good news. The CIR Expert Panel reviewed glycyrrhetinic acid, glycyrrhizic acid, and their salts and esters and concluded they’re safe as used in cosmetics — no meaningful signal for irritation, sensitization, phototoxicity, or mutagenicity at cosmetic-use concentrations. This is one area where the hype and the data actually align.
On pseudohyperaldosteronism — and why you can ignore that scare
You may have seen warnings that licorice can cause pseudohyperaldosteronism (a serious electrolyte disturbance). Those cases come exclusively from chronic high-dose oral licorice consumption — think black licorice candy or herbal supplements. Dermal penetration from topical cosmetics is negligible. Topical licorice and oral licorice are, safety-wise, entirely different conversations.
Regulatory treatment varies. In the US, licorice-derived actives in skincare fall under cosmetic or medical-device status — not OTC drug monographs. Japan and several Asian jurisdictions classify specific fractions (glabridin-enriched oils, dipotassium glycyrrhizate) as quasi-drug actives, which means slightly higher manufacturing standards. It’s a reasonable heuristic: if the product is Japan-made or Korea-made and flags a specific constituent rather than “licorice extract,” you’re more likely getting a standardized dose.
Who this ingredient family works for — and who should look elsewhere
Worth including for
- Mild melasma or uneven tone — as part of a combination formula with vitamin C or niacinamide
- Sensitive skin that reacts to hydroquinone or stronger depigmenting actives
- Mild atopic dermatitis looking for a steroid-sparing maintenance option
- Post-shave irritation or mild UV erythema (licochalcone A specifically)
- Anyone prioritizing well-tolerated, long-term botanical support over fast results
Look elsewhere if
- You want a true hydroquinone alternative for stubborn melasma — tranexamic acid or thiamidol have stronger data
- You’re treating moderate-to-severe rosacea — metronidazole, azelaic acid, or ivermectin have real RCTs
- You’re buying specifically for glabridin’s “16× hydroquinone” claim — that number doesn’t mean what the label implies
- You need visible results in under 4 weeks — botanical timelines are slower
- You have a known licorice or Fabaceae plant allergy — rare but documented
Research citations
K Brand Ingredient Proof — Final Verdict
A solid supporting actor, not the lead.
Licorice is one of the safer and better-tolerated botanical families in skincare — and when you look at the individual constituents, some of them (liquiritin, licochalcone A, glycyrrhetinic acid) have real, if modest, clinical footing. The problem is that marketing lumps all five into one hero ingredient and then leads with the constituent that has the least independent human data (glabridin). Buy licorice as a thoughtful combination partner with vitamin C, niacinamide, or a mild AD emollient. Don’t buy it expecting hydroquinone-level depigmenting or prescription-level rosacea control — the evidence doesn’t carry those claims. A supporting actor, not the lead.
K Brand Ingredient Proof ratings are based on published peer-reviewed literature, CIR safety assessments, and NCBI-indexed clinical trials — not personal product testing. This article is for educational purposes and does not constitute medical advice. Always consult a dermatologist for clinical skin concerns such as melasma, atopic dermatitis, or rosacea. This article may contain affiliate links. Full disclosure →
