Kojic acid is a skin-whitening, de-pigmenting agent and an antioxidant (protects cells from free radicals that can damage them) used as an ingredient in cosmetic products. The Japanese discovered kojic acid more than 20 years ago and it has been used in foods such as miso, sake and soy sauce. Kojic acid is also used as a food additive to prevent enzymatic browning. Kojic acid is naturally produced from fungus such as aspergillus, a mushroom found in Japan.
How It Works
According to Kojicacid.org: "This natural mushroom extract is an extremely popular skin-lightening treatment." Kojic acid can dramatically lighten the skin, improve age spots and lighten freckles. Kojic acid works by blocking the enzyme tyrosinase, which is necessary for the production of melanin in the skin. Melanin, or pigment, gives us the natural color to our skin, hair and the irises of our eyes. Kojic acid is also available as a cream, lotion, serum or soap.
Is It Safe?
According to Kojicacid.org, "there have been many claims in regard to this compound being a safe product to use on the skin. It has been said that although it does not appear to have carcinogens, which are known to cause cancer, it does seem to have an effect on a number of people's skin who had used it regularly and for extended periods of time." After using a kojic acid product for an extended period, sensitivity may develop, which could cause contact dermatitis. The kojic treatment will need to be stopped to heal the dermatitis.
How to Use
Discuss with your doctor or pharmacist and read the product label as to how to use the product. Usually it is applied topically to the skin either as a lotion, cream or serum. A kojic acid soap may also be used to wash the face. The lower the concentration of kojic acid in the product, the lesser the chances of skin sensitivity. A 0.2 percent concentration is used in most products. The maximum concentration of kojic acid is usually 1 percent.
Considerations
Before using kojic acid products, discuss with your doctor or pharmacist any medications you may be taking, including any herbal or over-the-counter drugs, to avoid drug interactions. Check the product label to be sure you are not allergic to any of the ingredients contained in the product. Keep in mind that to maintain the skin-lightening effects of kojic acid treatment, the product must be used on a regular basis.
Studies
According to Globalflavour.com, "a 1999 study in Japan showed that kojic acid at very high doses given orally to rodents caused some stimulation of thyroid cells by increasing TSH (thyroid stimulating hormone)." Another study, also using extremely high oral doses of kojic acid in rodents, showed a slight increase in stimulating liver cells to develop benign adenomas (tumors). Further studies are being done.
