Is Kojic Acid Safe For Long-Term Skin Whitening?

Medically reviewed by Martha Juco, MD · Aesthetics

Written by Hello Doctor Medical Panel · Updated Dec 12, 2022

    Is Kojic Acid Safe For Long-Term Skin Whitening?

    Kojic acid can be used to repair scars and hyperpigmented skin, but you shouldn’t try to lighten your skin naturally with it. The main applications of kojic acid in cosmetics are based on its antioxidant, antiproliferative, anti-inflammatory, UV protection, and skin-lightening properties. Make an appointment to see your dermatologist if you wish to utilize products containing kojic acid to treat a specific condition or improve your appearance. They can advise you on the best and safest course of action and can also give you information on dose and complementary therapies.

    Benefits of kojic

    Kojic’s acid primary use and benefit is to lighten visible sun damage, age spots, or scars. This can result in an anti-aging effect on the skin.

    In addition to skin-lightening effects, kojic acid also contains some antimicrobial properties. It may help fight off several common types of bacterial strains even in small dilutions. This can help treat acne caused by bacteria in the skin. It may also lighten scars from acne that haven’t faded yet.

    Kojic acid also has antifungal properties. It’s even added to some antifungal products. It may be useful in treating fungal infections of the skin like yeast infections, candidiasis, and ringworm or athlete’s foot. If soap containing kojic acid is used regularly, it may help prevent both bacterial and fungal infections on the body.

    Kojic acid in cosmetics

    The most important uses of kojic acid in cosmetics are as follows:

    Kojic acid is used as a bleaching agent and to protect the skin against the effects of ultraviolet rays in cosmetic products. It’s also used as a teeth whitening ingredient in oral care products.

    Several studies have been performed to evaluate the mechanism of pigmentation reduction and the safety of kojic acid in cosmetics. Accordingly, the best recommended concentration range for topical kojic acid preparations is 1% or less to ensure efficacy and safety.

    Besides that, another benefit of kojic acid has been showing antibacterial properties that can kill some common bacteria (e.g. acne-causing bacteria) even in small dilutions. Studies have also shown that kojic acid has the ability to fight fungi that live and cause disease on the skin.

    Kojic acid side effects

    In addition to the benefits, a number of adverse reactions may also be associated with kojic acid when used in cosmetic products.

    Among them, contact dermatitis (especially on people with sensitive skin) is the main side effect of kojic acid. Manifestations of contact dermatitis when using kojic acid are irritation, rash, dermatitis, itching, and pain. However, these side effects can be observed in cases of improper use of kojic acid and abuse of kojic acid such as taking in concentrations higher than 1%.

    Another side effect that can appear with long-term use of kojic acid is sunburn in people with sensitive skin. In addition, there is some evidence that kojic acid can also lead to skin cancer on damaged skin. However, further studies are still needed to determine other potential benefits or risks of kojic acid.

    Is it safe for skin?

    Despite its “acid” moniker, kojic acid is safe to use. Though it’s not recommended to use it to lighten your complexion. While you may notice some bleaching effects, your skin will eventually shift back to its natural state once you discontinue use. Using excessive amounts of the ingredient can cause some serious irritation. Instead, use kojic acid-infused products to fade age spots, sun spots, or those post-breakout marks.

    Who can benefit from kojic acid use?

    If you have a tendency to have an uneven and pigmented complexion, kojic acid could be very beneficial to you. It works well on pigmentation from sun-damage, melasma, or the common post-inflammatory pigmentation, dark spots that occur after acne, bug bites, or injuries. It can even improve under eye circles that are a result of hyperpigmentation. Though it won’t do much for puffiness, hollowing, or thin skin with visible blood vessels.

    Key Takeaway

    When using kojic acid topically, you’ll likely start to see results within two weeks. You may see greater results — or faster results — if you also add glycolic acid to the treatment. Consult your dermatologist.

    You can use kojic acid to treat areas of hyperpigmentation or scarring, but you shouldn’t use it in an attempt to lighten your natural complexion.

    If you want to use products containing kojic acid to treat a certain condition or cosmetic appearance, make an appointment to see your dermatologist. They can help you decide the best and safest course of action. They can also provide you with information about dosage and complementary treatments.

    If you experience any redness, rashes, irritation, or pain when using kojic acid, stop using it immediately. To soothe immediate irritation, you can apply over-the-counter hydrocortisone cream to the affected area. However, caution should be observed when using these; long-term use may lead to untoward effects. Always consult your dermatologist.

    Learn more about Skin Care and Acne here.

    Hello Health Group does not provide medical advice, diagnosis or treatment.

    Medically reviewed by

    Martha Juco, MD


    Written by Hello Doctor Medical Panel · Updated Dec 12, 2022