Licorice root extract

What it is

Licorice root is the sweet root of Glycyrrhiza glabra, a legume grown across southern Europe and Asia. Two of its compounds matter for skin. Glabridin inhibits tyrosinase, the enzyme that drives pigment production, and in animal skin it also reduced the pigmentation and redness that follow UVB exposure³. Liquiritin is the component used in most melasma trials and appears to help disperse pigment that is already there¹. On labels, look for "Glycyrrhiza glabra root extract", "licorice extract", "glabridin" or "dipotassium glycyrrhizate".

What the evidence says

Evidence: limited. A few small trials, mostly short and without placebo control, suggest licorice compounds lighten melasma and dark marks; no large randomised study exists.

The most cited trial treated 20 women with melasma with liquiritin cream on one side of the face and a plain cream on the other, twice daily for four weeks, with sun avoidance throughout; most showed a clear improvement on the liquiritin side². A 2018 systematic review of natural ingredients for hyperpigmentation gathered this and a handful of other licorice studies, including small comparisons with hydroquinone, and concluded the results are promising but limited by small numbers, short follow-up and a lack of long-term safety data¹. The NIH notes preliminary evidence that topical licorice gels may help eczema symptoms and burn healing, while warning that topical use can irritate some people⁴. For how it compares with azelaic acid, niacinamide and vitamin C, read dark spots and hyperpigmentation and melanin-rich skin care.

How people use it

• A serum or cream with licorice extract or glabridin, typically around 0.5%⁵, once or twice daily on dark marks or the whole face.
• Combined with niacinamide, vitamin C or azelaic acid, which act on different steps of pigment formation.
• Always under a daily broad-spectrum sunscreen; without it, no brightening ingredient can keep up.
• As a calming ingredient in moisturisers for sensitive or easily reddened skin.

Cautions

• Patch test. Topical licorice can cause irritation in some people⁴.
• The serious warnings about licorice (raised blood pressure, irregular heartbeat, risks in pregnancy) relate to eating or drinking glycyrrhizin-containing licorice, not to creams⁴. Do not take licorice supplements for your skin.
• Expect slow, partial change over two to three months, not an even tone in weeks.
• A dark patch that is changing shape, bleeding or growing is not hyperpigmentation until a professional says so; see when to see a dermatologist.