Kojic acid and derivatives present cytotoxicity to some cancerous cell lines, including melanoma, hepatocellular carcinoma, ovarian cancer, breast cancer and colon cancer. Regarding safety, kojic acid or its derivatives are safe molecules for human use in the concentrations tested.
Kojic acid is not known to cause skin cancer.
Kojic acid was deemed a “quasi-drug” and banned from the market in Japan by the Ministry of Health, Labor and Welfare in 2003 and subsequently in Korea and Switzerland due to safety concerns stemming from animal test results suggesting mutagenicity.
Though kojic acid soaps can work on most skin types, experts say that those with sensitive or dry skin should be cautious as it may sometimes cause irritation. “Those with dry skin may want to opt for soaps with moisturizing properties,” advises Dr. Gohara. “Always do a patch test before using it regularly.”
Avoid using concentrated kojic acid on your skin daily if you have hypersensitive or reactive skin. It can make your skin more sensitive to sun damage. Therefore, always follow up with sunscreen during the day. It can also dry or irritate your skin if you have allergies or sensitivity.
Kojic Acid can make your skin more sensitive to the harmful effects of sunlight. Hence it is advised to use sunscreen and wear protective clothing while using Kojic Acid. It is recommended to avoid tanning booths and sunlamps.
One of the most popular beauty ingredients from South Korea, Kojic acid has many beauty benefits.
The Food and Drug Administration (FDA) warns all healthcare professionals and the general public NOT TO PURCHASE AND USE unauthorized cosmetic product, KOJIC ORIGINAL.
Some studies indicated that kojic acid can be more irritating to the skin compared to hydroquinone. ¹² This means individuals with sensitive skin may find hydroquinone to be a more suitable option. In summary, both hydroquinone and kojic acid can be effective for lightening dark spots.
Potential Endocrine Disrupting Properties
Data suggests that kojic acid may disturb the synthesis of thyroid hormones by suppression of iodine uptake and subsequent organification (SCCS, 2022; Higa et al., 2002; Tamura et al., 1999).
Potential Health Hazards: Eyes: Causes eye irritation. Inhalation: May be harmful if inhaled. Causes respiratory tract irritation. Skin: Causes skin irritation.
On the other hand, certain ingredients can trigger irritation and should be avoided if you're using kojic acid in your skincare routine. Harsh acids, like alpha-hydroxy acids (AHAs), are a prime example, as well as certain retinoids.
Yes, it is generally okay to use kojic acid daily, but it should be done cautiously. Start using it a few times a week to see how your skin reacts, gradually increasing to daily use if no irritation occurs. Always follow up with a moisturizer and sunscreen, as kojic acid makes your skin more sensitive to the sun.
Glycolic Acid
It is an alpha-hydroxy acid (AHA) derived from sugarcane. In low concentrations, glycolic acid produces desquamation of pigmented skin cells. About 30 to 70 per cent of glycolic acid can enhance the penetration of other skin lighteners such as HQ.
... KA is listed as an 'additive' in the Inventory of Cosmetic Ingredients database of Europe, and in countries such as Switzerland, there is a ban on the use of KA as a cosmetic ingredient [13].
Dermatologists we spoke with confirm kojic acid can, indeed, be used to lighten skin, as well as treat dark spots and acne scars. Kojic acid also has anti-aging and antioxidant properties. Yep, it's the holy grail of soaps.
Alpha Arbutin has comparatively fewer risks than many whitening ingredients, including kojic acid, making it effective for dark spots and melanin overproduction.
Finally, all Kojie San products come with a unique sticker with a scannable QR code on the packaging to verify its authenticity. However, these codes cannot just be scanned by your regular phone camera. You will need to download the Hidden Tag application on your phone in order to scan it.
Japanese beauty routines are renowned for their emphasis on clear, luminous skin, and one of the secret ingredients that has been gaining international acclaim for its effectiveness is Kojic acid.
Kojic acid's properties allow it to be a bleaching agent when used in creams, gels, and other cosmetics. Kojic acid is similar to a chemical called hydroquinone. They are both effective treatments for hyperpigmentation. Treatment with kojic acid isn't immediate.
Laser Treatments
Many Asians seeking safe and effective solutions for skin concerns like melasma, freckles, Hori's Nevus, and solar lentigo, are opting for laser treatments for their pigmentation.
If you stop using kojic acid, your skin may gradually return to its original state, particularly if the underlying causes of hyperpigmentation are not addressed. To maintain the results, it's important to integrate kojic acid into a continuous skincare routine.
Both are available over the counter and inhibit melanin production. However, Kojic acid is considered more potent and is thus a preferred choice for more stubborn hyperpigmentation.
Kojic acid is produced by various strains of Aspergillus and Penicillum. It is found in very low concentration in traditional Japanese foods such as miso, soy sauce and saké. Kojic acid is also used as an additive for preventing enzymatic browning and for cosmetics.