Kojic acid is used in health and beauty products to whiten the skin. It can be used in skin care and cosmetic products for areas such as sunburn, scars, and age spots. The science behind how kojic acid works as a whitening agent involves its effect on melanin production. Kojic acid can be added to existing lotions and soap bases or combined with hyaluronic acid to create a gentle and effective whitening serum. Products containing kojic acid can be applied to the face, chest, hands, elbows, thighs, or anywhere whitening is desired.