Kojic Acid Is the Dermatologist-Loved Ingredient For Fading Dark Spots

You're likely already familiar with glycolic and salicylic acids, but even if their names don't ring a bell, they're popular enough ingredients that you're probably using products with them in your beauty routine. Still, there are lesser-known ingredients that deserve their time in the skincare spotlight, particularly if your goal is a brighter, more even complexion. One of which is kojic acid—a naturally derived skincare ingredient that comes from the superfood mushrooms.

Kojic acid is excellent at fading hyperpigmentation and discoloration (aka dark spots). And it works just as well on its own and as it does when paired with other brightening ingredients. Plus, it serves as an antioxidant and has anti-inflammatory properties. To help you incorporate this somewhat under-the-radar ingredient into your current skincare routine, we asked top dermatologists to give us the lowdown on all things kojic acid.

Read on to learn how the experts recommend using kojic acid to say goodbye to dark spots for good.

What is Kojic Acid?

Kojic acid is a naturally derived ingredient primarily recognized for its ability to brighten the skin and reduce hyperpigmentation, making it great for fading dark spots, acne marks, and sun damage over time.

"Because it comes from natural sources like mushrooms and fermented rice, it’s generally well-tolerated, even by sensitive or reactive skin," says dermatologist, Alexandra Bowles, DO. "Plus, it brings antioxidant and antimicrobial benefits that calm inflammation while supporting a more even, radiant complexion. I often recommend using it alongside vitamin C or niacinamide for a gentle, balanced approach to brightening."

How Does It Work?

"Unlike other acids that work by dissolving the bonds between the cells and exfoliating the skin, kojic acid works by inhibiting pigment production," she says. It also works well when paired with other skin-lightening ingredients (namely, the gold standard hydroquinone, most commonly prescribed by derms).

Dermatologists often combine it with hydroquinone for a synergistic, prescription-strength lightening agent, notes dermatologist, Dhaval Bhanusali, MD. But on the flip side, it works well on its own, too, and is a great alternative for those who can't tolerate or don't want to use the more potent hydroquinone. "It's also less likely to cause an overly-white appearance of the skin, making it a good option for people with darker complexions who'd be more likely to [experience extreme lightening] from using other ingredients," says dermatologist, Rachel Nazarian, MD.

Benefits of Kojic Acid for Skin

Spot-fading and skin brightening is the name of the game for this ingredient, though it does have a few other standout qualities, such as:

• Inhibits the production of melanin in the skin: The pathway that leads to excess melanin or pigment (in other words, a dark spot) is complex, but at the heart of the matter is an enzyme known as tyrosinase. Kojic acid blocks the UV activation of tyrosinase, thereby limiting melanin production. This means it can help lighten existing sunspots and photodamage, fade the dark marks left from acne scarring or after a pimple, and even improve melasma, says dermatologist, Y. Claire Chang, MD.
• Acts as an antioxidant: Kojic acid can help scavenge and counteract skin-damaging free radicals caused by exposure to UV damage and pollution. This not only helps improve overall skin tone but also makes it a good general anti-aging ingredient, says Dr. Nazarian.
• Has anti-inflammatory and anti-viral properties: Unlike many other acids, it also has these unique characteristics, though they're secondary to the skin-lightening benefits.

What Products Contain Kojic Acid?

Kojic acid can be found in numerous cosmetic formulations, including powders, serums, masks, creams, cleansers, and soaps.

Is Kojic Acid Safe For All Skin Types?

According to the experts, kojic acid is safe for most skin types. Anyone seeking to improve the look of discoloration caused by sun damage, melasma, or post-inflammatory hyperpigmentation that occurs after a blemish, would benefit from kojic acid most, says Dr. Chang. Dr. Bhanusali adds that it's also a good option for those who want to avoid or can't tolerate hydroquinone, one of the most often-used skin-brightening ingredients.

Potential Side Effects

"Generally speaking, kojic acid is better tolerated than most acids, but an allergy or irritation is certainly possible," points out Dr. Bhanusali. A red rash, itching, irritation, and burning are the most common side effects, adds Dr. Chang, though these are typically uncommon if you're using lower concentrations of the ingredient (and most over-the-counter products do contain a lower concentration). "There's also a risk of contact dermatitis, so a patch test is recommended before full application," she adds. If irritation persists, consult with a board-certified dermatologist. Dermatologist, Tiffany Libby, MD, advises caution for those with sensitive skin to begin with low-dose formulations.

How to Use It

If your skin is super sensitive, Dr. Nazarian recommends not using it daily at first; instead, work kojic acid-based products into your regimen just once or twice per week to ensure that your skin can tolerate the ingredient. Also worth noting: "When used over time, kojic acid may also make your skin more susceptible to the sun," says Dr. Chang. Using sunscreen daily is always important, but even more so when kojic acid is in your skincare mix.

Frequency of use depends on what other ingredients it's compounded with and the concentration, but generally, it can be used daily. "When adding kojic acid to your routine, pair it with a calming moisturizer to support your skin barrier," says Dr. Bowles. "Apply it after cleansing but before heavier creams or oils for best absorption and results."

According to Dr. Nazarian, studies have shown that kojic acid works well with and enhances the effects of glycolic acid and hydroquinone. While kojic acid does have a synergetic effect when used with these other brightening exfoliating ingredients, pairing it with these also increases the likelihood of experiencing excessive dryness or irritation. Proceed with caution and start using any products containing kojic acid and other actives gradually, giving your skin time to acclimate.

Alternative Ingredients

There are numerous ingredients on the market other than kojic acid that may help fade hyperpigmentation, dark spots, and acne scars, including:

• Glycolic acid is an alpha-hydroxy acid that loosens bonds between dead skin cells. It helps stimulate collagen production and acts as a humectant, attracting moisture to the skin.
• Retinol is a vitamin A derivative that helps promote skin cell turnover and boosts collagen production. In doing so, it helps even skin tone and texture, helping to reduce discoloration.
• Hydroquinone is a topical skin treatment that lightens hyperpigmentation, age spots, and freckles while evening out skin tone.
• Arbutin is a natural derivative of hydroquinone that fades dark spots, hyperpigmentation, and acne scars.
• Vitamin C helps fade dark spots and boosts sunscreen efficacy, helping prevent future dark spot formation.
• Niacinamide soothes inflammation while brightening and smoothing skin.
• Azelaic acid is another good choice. It helps fade pigmentation and fights bacteria, which is great for acne-prone skin, according to Dr. Bowles.
• Licorice root extract offers natural brightening and calming benefits, adds Dr. Bowles, making it ideal for sensitive skin types.