Kojic acid is a chemical produced from different types of fungi. It is also a by-product of fermented soy sauce and rice wine. Possible benefits include treating melasma, reducing the appearance of scars, and more.

Kojic acid is sometimes used in the food industry as a natural preservative. One of the main uses of kojic acid, however, is in some health and cosmetic products.

The benefits of using products containing kojic acid may include the following:

Anti-aging effect: Products containing kojic acid may lighten the skin, which can improve the appearance of age spots and sun damage. The reduction of dark spots can have an anti-aging effect.
Treat melasma: Kojic acid may also be helpful in decreasing melasma, which is darkening of the skin due to pregnancy.
Decrease the appearance of scars: Kojic acid may also reduce the discoloration of scars. Although the acid does not improve the thickness of scar tissue, it may reduce dark pigmentation associated with certain types of scars. Lightening the scar may make it less noticeable.
Antifungal benefits: Kojic acid is also thought to have some antifungal benefits. It may be helpful in preventing and treating certain fungal infections, such as athlete’s foot and yeast infections.
Antibacterial effects: Kojic acid may also provide antibacterial benefits. It may help decrease the chances of developing common types of bacterial skin infections.