Brighteners
Kojic acid
Also listed as Kojic dipalmitate (more stable ester)
Kojic acid is a compound made by fungi during the fermentation of rice (sake and soy production) and used in soaps, creams and serums to fade dark spots. It works but is unstable and a known, if uncommon, cause of skin allergy.
What it does
The short version.
Kojic acid binds copper in the tyrosinase enzyme, reducing melanin production, and it also has antioxidant activity. It is usually combined with other brighteners such as niacinamide or arbutin. Pure kojic acid darkens and loses activity on exposure to light and air, so esters like kojic dipalmitate are often used for stability.
Emerging evidence
Lab data are robust, but clinical trials are small and usually test kojic acid in combination with other agents, so its effect on its own is hard to isolate.
Reach for it for
Usually a good fit for
How to use it
Getting it right.
Use once or twice daily on areas of concern, or as a short-contact soap that is rinsed off, and wear sunscreen daily.
Layering
Friends & frenemies.
Pairs well with
Go slow with
Not forbidden — just easier to over-do. Alternate nights or separate morning and evening.
Before you start
Can cause contact dermatitis and irritation, more often at higher concentrations or on sensitive skin. Patch test first. Very strong 'whitening' soaps sold online may contain undisclosed ingredients; buy from reputable sellers.
References
- 1Kojic acid applications in cosmetic and pharmaceutical preparations — Biomedicine & Pharmacotherapy (2019), via PubMed
- 2Biological activities and safety data of kojic acid and its derivatives: A review — Experimental Dermatology (2022), via PubMed
Educational, not medical advice. Ingredient guides summarise published research and expert guidance; formulas and concentrations differ between products.
No kojic acid products reviewed yet.
We add products every week. The guide above still stands — and Beauty Match can find what suits you today.
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