Licorice (Glycyrrhiza glabra)

Ingredient context

Licorice's role in FADE is pigmentation, not texture. Its key compound, glabridin, is a well-characterised tyrosinase inhibitor, tyrosinase being the rate-limiting enzyme in melanin production. In-vitro comparisons have found glabridin's skin-lightening activity to be markedly stronger than hydroquinone on a like-for-like concentration basis.

Evidence context

In a single-centre, double-blind clinical study, a hydroquinone-free brightening formula built around glabridin produced greater improvements in UV-induced hyperpigmentation than a 4% hydroquinone cream, with the added advantage of Licorice's comparatively low irritation profile. A second compound in Licorice, liquiritin, works differently: rather than blocking melanin production outright, it disperses existing melanin more evenly across the skin.

This is part of why Licorice appears repeatedly across clinical trials for melasma. A scoping review of herbal melasma treatments identified it as the single most extensively studied botanical for the condition.