Everything You Need To Know About Kojic Acid
Kojic acid is a compound made by fermentation in fungi like Aspergillus and Penicillium. Fermented soy and rice products, like miso, soy sauce, and sake, naturally produce kojic acid.
Kojic acid is often used in skin-lightening products because it reduces skin pigmentation by blocking melanin production. This molecule gives color to the skin, hair, and eyes, but it’s also the cause of hyperpigmentation.1
Kojic acid is also used in some medications to treat skin conditions, such as melasma. Keep in mind that it can cause sun sensitivity and skin conditions like contact dermatitis, redness, and flares.2
Uses
Kojic acid has been used in the cosmetic, pharmaceutical, and food industries:
Cosmetics: Some cosmetic products use 0.4-4% kojic acid as a skin-lightening agent and to increase their shelf life.32 Kojic acid products are among the most expensive skin-lighteners, costing more per ounce than vitamin C and retinol products.4
Dental care products: Kojic acid can be used in dental products, like tooth-whitening patches.5
Medical: Kojic acid can help treat melasma, a condition that causes hyperpigmentation in the skin.5 Other medications, such as antimicrobial drugs, also contain kojic acid.6
Foods: Kojic acid has antioxidant properties. It is used as a food additive to preserve fresh vegetables, seafood, oils, flour, and syrup.67
Benefits
Kojic acid can improve skin hyperpigmentation. In a study of the effects of 3% kojic acid on post-acne skin, participants had increased skin brightness and decreased contrast.8
Kojic acid formulations are sometimes given as a topical adjuvant (additional treatment) to hydroquinone treatment, the most common treatment for melasma. While kojic acid can be prescribed in the United States for this treatment, the European Union, Australia, and Japan have banned it due to safety concerns.9
Other agents can be prescribed alone or in combination with hydroquinone to treat melasma.10 A meta-analysis indicated that kojic acid alone may improve melasma.5
Kojic acid may also have antimicrobial, anti-inflammatory, and antioxidant effects—though studies showing these benefits on human skin are limited.1
How To Use Kojic Acid
Kojic acid is mainly found in creams, serums, lotions, soaps, eye creams, sunscreens, and face washes at 0.4-4% concentrations.3 You can incorporate kojic acid products into your skincare routine to improve dark spots.11
Here are a few tips on how to use kojic acid products:
Use products with a maximum of 1% kojic acid: It is safer to use products with a maximum of 1% kojic acid unless your dermatologist advises otherwise.7
Try on a small area: Apply the product to a small patch of skin and monitor for a few days for any skin reactions. If your skin starts to itch or burn or a rash forms, stop using it and consult a dermatologist. Some products can cause irritation when during long-term use.
Always use sunscreen: Kojic acid and other skin-lightening agents can increase sun sensitivity. Sunscreen will help protect your skin from potential irritation and sun damage.2
Avoid using it on broken skin: Kojic acid is intended for topical use. If you have broken skin, wait until your skin has recovered before using kojic acid.2
Safety and Side Effects
According to the Scientific Committee on Consumer Safety, kojic acid is safe for cosmetic products at a concentration of up to 1%.7
Skin-lightening agents have gained popularity, leading to inappropriate sales and use of products for lightening skin tone. A study showed that while about 73% of people use skin-lightening agents to treat skin conditions, around 27% use them for general skin-lightening, and only about 23% consult a healthcare provider.1213
Pollock S, Taylor S, Oyerinde O, et al. The dark side of skin lightening: An international collaboration and review of a public health issue affecting dermatology. IJWD. 2021;7(2):158-164. doi:10.1016/j.ijwd.2020.09.0
Cosmetic products, including kojic acid, can cause skin conditions in some individuals. One case study found that face cream caused itching and burning in an individual. Tests confirmed it was due to the product’s 1% kojic acid, so be careful with kojic acid products if you have sensitive skin.14
Choosing a Kojic Acid Product
If you decide to buy a kojic acid product:
Use 1% kojic acid at most: The safety of higher kojic acid concentrations is not yet known.7
Check your other skincare products: You may already be using skin-lightening agents, such as azelaic acid, tranexamic acid, retinoids, and hydroquinone. Before adding another, remember that overusing them can cause long-term health and skin problems.13
Don’t buy homemade creams or products from unknown sellers: Skin-lightening products, including kojic acid products, can contain heavy metals and steroids.15 Steroids can improve skin conditions but should only be used with a prescription from a healthcare provider.16 Cosmetics don’t require U.S. Food and Drug Administration (FDA) approval, meaning there may be unsafe products on the market from irresponsible manufacturers.15 Avoid purchasing kojic acid products online from unknown sellers.
A Quick Review
Kojic acid can reduce skin hyperpigmentation, which is why it is commonly used in many skin-lightening cosmetics. It can also be used to treat melasma.
If you’re purchasing kojic acid products, choose one with a maximum concentration of 1% kojic acid, as the safety of higher concentrations is unknown. If you have sensitive skin, consult your dermatologist before using kojic acid—it can cause irritation and other skin conditions.
DQH Knowledge drop: In your 20s, your skin cell turnover decreases. (Cell turnover is a key component in keeping your skin youthful.) You know what else slows down? Your collagen production. Starting in your 20s, collagen decreases by about 1 percent per year. Should you want to prevent fine lines and wrinkles, start by eliminating behaviors that contribute to premature aging. “If it’s bad for you, it’s bad for your skin,” says dermatologist Michel Somenek.
“Cigarette smoking reduces blood flow to the skin and causes premature wrinkling and a dull skin texture. Making the repeated pursed motion to inhale can also cause smoker’s lines. Alcohol and recreational drugs are toxins for the skin that damage its cellular structure and DNA,” Somenek tells us. “The faster you eliminate vices while you are young, the better chance your skin and body have to recuperate.” Also, adopting an anti-aging routine in your 20s is key. After all, the best offense is a good defense. We spoke to Somenek and experts Joshua Ross and Audrey Kunin to find out more.
Keep reading for the best anti-aging products for your 20s, according to skincare professionals.
Sunscreen
“We all know that the sun is the number one cause of skin aging and starting the prevention in your 20s is very important,” Ross says. “The majority of your sun damage won’t start to appear until you’re in your 30s, so don’t wait until you see it surface or you’ll be behind the curve. Stay ahead of it with a good-quality zinc-based sunscreen worn daily.”
Farmacy Green Defense Daily Mineral Sunscreen
An invisible sunscreen with SPF 30, plus botanical extracts meant to protect skin with tons of antioxidants. Bonus: It’s clean and fine to use under makeup.
Bareminerals Complexion Rescue™ Tinted Moisturizer Broad Spectrum SPF 30
Although we recommend you use your SPF and moisturizer separately, we also understand moments when you don’t have time or energy for that extra step. For those times, this bareMinerals moisturizer is a great thing to have on hand.
Vitamin C Serum
“A great introduction to anti-aging is to start with a vitamin C serum in your morning skincare routine,” Ross says. “It’s a powerful antioxidant that will neutralize free radicals and brighten the skin.” He adds that it’s a great way to counteract the effects of the sun’s harmful rays, which, as previously mentioned, are among the biggest causes of premature aging.
Drunk Elephant C-Firma™ Vitamin C Day Serum
The Drunk Elephant C-Firma is a lightweight serum that promises to give skin a glow by combining the brightening powers of vitamin C with ferulic acid, l-ascorbic acid, and vitamin E. The included sodium hyaluronate is meant to replace hydration loss, so you shouldn’t have to deal with any irritation.
Sunday Riley C.E.O. Rapid Flash Brightening Serum
This potent serum is jam-packed with vitamin C (15 percent, to be exact), which means it’s a potential superstar at both brightening skin and dousing it in antioxidants.
Peptides
Using peptides on your skin has many benefits, says Somenek. “The skin barrier is what defends the body against pollution, UV rays, bacteria, and toxins. It can be damaged by several everyday factors. Using topical peptides aids in building a stronger barrier,” he says. “Peptides comprise elastic fibers, which are a type of protein. These fibers help to make skin appear taut and firm. Peptides can also help repair damaged skin, relieve inflammation, and even out skin tone. Some peptides can kill acne-causing bacteria that is common in 20-somethings.”
Kunin agrees, saying, “Peptides are an excellent entry point for supporting collagen.” She recommends looking for face and eye treatments that contain these collagen-boosting powerhouses.
Charlotte Tilbury Magic Eye Rescue Cream
This Charlotte Tilbury super-emollient eye cream has a base of coconut oil and shea butter (read: it’s incredibly hydrating). Botanicals plus peptides are meant to help reduce dark circles and boost collagen, respectively.
This creamy moisturizer serves up potent collagen-boosting peptides and pycnogenol, and antioxidant-rich vitamin C. “Instead of sitting on top of the skin, peptides penetrate the outer layer so they go deep. The ‘signals’ they send tell the cells to produce elastin and collagen, which are needed for youthful-looking skin,” explains Somenek.
At-Home Peel Pads
Remember that skin cell turnover fiasco we talked about earlier? One way to help support it is by exfoliating. “Exfoliation is important to help keep skin fresh and luminous,” Kunin says. She recommends using at-home peel pads as an easy and effective way to exfoliate.
“The goal in your 20s is to fight the slowing pace of cell turnover. It is wise to use products that gently exfoliate, yet still remove oil and other impurities. Products that have Alpha Hydroxy Acids (AHA) or Beta Hydroxy Acids (BHA) are a good choice.”
According to Somenek, you should only exfoliate two to three times a week. “People of all ages are guilty of over-exfoliating and that can be too much of a good thing,” he says.
Dermadoctor Kakadu C Intensive Vitamin C Peel Pad
A few swipes of this Derma Doctor powerful peel pad promise to leave your skin glowing and smooth, thanks to the seven (yes, seven) types of chemical exfoliants, including AHA and BHA. It also contains vitamin C via Kakadu plum extract for added brightening and antioxidant protection.
KEY INGREDIENTS Kakadu plum extract is sourced from the Kakadu plum, a fruit grown in northern Australia. It contains vitamin C, which restores the skin’s natural barrier, increases collagen production, and soothes irritation.
Dr. Dennis Gross Skincare Alpha Beta® Universal Daily Peel Pads
These are the gold standard of peel pads, with a cult following and over 900 five-star reviews on Sephora. They’re easy to use and contain a blend of anti-aging exfoliating acids.
Emollient Night Cream
“In your 20s, you need to start upping the hydration in your skincare routine. You may have been cautious of over-moisturizing because of acne in your teens, but as you enter your 20s, your skin transitions and becomes drier,” Ross says. “I recommend an emollient night cream added into your evening skincare regimen.”
“Twenty-somethings need to make sure that they are not using creams that will clog their pores and cause excess oil production,” says Somenek. Opt for non-comedogenic products.
Cerave Skin Renewing Night Cream
One great choice is the CeraVe Skin Renewing Night Cream, which is a non-comedogenic night cream that leaves skin soft and glowy. It combines the moisturizing powers of ceramides and hyaluronic acid.
RoC Retinol Correxion Max Hydration Creme
“The best night cream ingredients contain retinol, benzoyl peroxide, and/or salicylic acid or hyaluronic acid. The goal is to moisturize, yet remove excess oil,” says Somenek. This Roc Retinol Correxion cream fits the bill as it contains both hyaluronic acid and retinol so it promises to moisturize while also being non-comedogenic.