"When it comes to beauty, what Americans consider luxury, Koreans consider maintenance," says Los Angeles–based Christina Han, former editorial director of the high-end beauty site Violet Grey and founder of the consulting firm Type Navy. "In Seoul, facials are part of the daily routine."

When it comes to innovation in the skincare world, I don't think anyone does it like Korea or Japan. If we're going to call New York City, Paris, Milan and London the fashion capitals of the world, we have to acknowledge Seoul as the beauty and skincare capital. From formulations to products and ingredients, k-beauty is where I look to better grasp what's new and hot in the skincare world. With that in mind, this post is not about ingredients that are new to everyone. These are ingredients that we have been seeing in k-beauty for years that have started to make an appearance in the formulations of western skincare products. Disclaimer aside, let's begin.

PHA's a.k.a polyhydroxy acids

Much like BHAs [betahydroxy acids] and AHAs [alpha-hydroxy acids], PHAs are a group of chemical exfoliants. Common PHAs used in skincare products include gluconolactone, lactobionic acid and galactose. They are second-generation alpha-hydroxy acids that work by exfoliating off the dead cells on the skin's surface to promote a more even tone and texture. PHAs stand out because of their molecular structure – they are much larger than their counterparts which means that they cannot penetrate as deeply into the skin. They work exclusively on the skin's surface which reduces the chance of them causing irritation. Additionally, their exfoliating properties help your other skincare actives penetrate deeper into the layers of your skin so you can truly get your money's worth.

PHAs also fight glycation; a process where a sugar attaches itself to the collagen in your skin and weakens it. This, along with their antioxidant properties helps promote skin plumpness and stimulate epidermal growth and repair. AHAs have an affinity for enhancing natural moisturizing factors, promoting that glow we all desire. Essentially, with PHAs you can get all the benefits of other chemical exfoliants and then some without as much irritation.

This chemical exfoliant may be for you if you have normal to dry skin or have found that your skin gets irritated with other exfoliating actives.

Get into it, yuh:

Glow Recipe's Watermelon Glow PHA+BHA Pore-Tight Toner

the Inkey List PHA Toner

Bakuchiol · [buh-KOO-chee-all]

Retinol is a holy grail in the skincare world however, it can be quite harsh on the skin and you do usually need to keep increasing the strength of the products you're using. I am a huge fan of this ingredient but even I have to admit that it is quite an intense skin commitment. That's why bakuchiol excites me. Bakuchiol is a plant-based ingredient extracted from the seeds and leaves of the babchi plant. Babchi is a herb that has been used in Ayurvedic, Chinese and traditional Indian practices to help heal, calm and soothe the skin due to its antibacterial and anti-inflammatory properties. "In a 2019 study, no difference was found between retinol and bakuchiol in treating wrinkles and hyperpigmentation. The retinol users, though, did experience more skin dryness and stinging." Similarly to retinol, bakuchiol catalyses the pathways that trigger the creation of several types of collagen making it useful for increasing skin health and promoting well-aging. It may also be potentially safe in pregnancy and breastfeeding unlike retinol which would be a gamechanger, however, many more studies need to be conducted to confirm that.

However, if you [like me] love retinol for its action on acne and breakouts, bakuchiol may not be as direct an alternative. Its soothing properties may come in handy for minimising breakouts but it doesn't have an as direct action on skin cell turnover and so may not reduce the frequency/ severity of your acne.

This may be the ingredient for you if you just love to try new things, cannot use retinol due to sensitivity or if you're a beginner at playing with skincare. If your skin can take it and has acclimatized to both ingredients alone, you may not have to choose between retinol and bakuchiol.

Get into it, yuh:

Paula's Choice Clinical 0.3% Retinol + 2% Bakuchiol Treatment

Herbivore Bakuchiol Retinol Alternative Smoothing Serum

Bondi Sands Fountain Of Youth Bakuchiol Serum

Tremella Mushroom

Tremella fuciformis, also known as snow mushroom, is a fungus that looks a little like the flower you'd stumble across if walking through a mystical forest. This mushroom is used in both skincare and cooking; having been used in desserts and dishes like Chinese snow fungus soup for thousands of years. If bakuchiol is the next retinol, then tremella is the next hyaluronic acid. Where hyaluronic acid can hold about 1,000 times its weight in water, tremella can hold approximately half that much which is still mighty impressive. Snow mushroom particles are smaller than those of hyaluronic acid so they can penetrate the skin layers more easily and take that hydrating power deeper into the skin. Like other mushrooms, tremella is rich in fatty acids with help in retaining moisture and stabilizing the skin barrier [like ceramides]. "Mushrooms are also rich in vitamins A, [also known as retinol], C, and D and have antioxidant and anti-inflammatory properties."

There is existing evidence that tremella may also contain kojic acid, an ingredient that has long been used as a skin lightener/ to aid with age spots and skin discolouration. Though what we know at this moment seems promising, there is a need for more research to be done on the clinical efficacy and usefulness of snow mushrooms in skincare.

The ingredient's gentle nature means that even the most sensitive can try it with low risk.

Get into it, yuh:

Humanrace Humidifying Cream

Herbivore Bakuchiol Retinol Alternative Smoothing Serum

Good Light Moon Glowy Milky Toning Lotion

Snail Mucin a.k.a. Snail Secretion Filtrate

Initial ick factor aside, snail mucin is a surprisingly effective skincare ingredient that is making its way into the routines of more and more people in the west [mine included]. Snail mucin or snail slime is used for its moisturizing and collagen-stimulating benefits. Now, you might be wondering exactly what it is – basically snail mucin is the product that snails excrete in stressful situations to protect themselves. There isn't currently a lot of research on this ingredient however, it does contain ingredients that *should* help the skin. Components of snail secretion filtrate include hyaluronic acid, allantoin, antioxidants, zinc, manganese, glycosaminoglycans, and growth factors—all good stuff for hydrating, plumping, soothing, and building collagen.

Since snail mucin is a stress-induced excretion, it has injury protective effects i.e. it contains things like growth factors that trigger the growth of new cells and new collagen which leads to fewer wrinkles and plumper skin. Allantoin, which I mentioned earlier is healing, helping to calm irritation, smooth skin and stimulate cell regeneration.

It is potentially universally beneficial to all skin types, especially those with dry skin due to its moisturizing benefits. Do avoid it if you are allergic to it or a vegan [since the ingredient is an animal product].

*I feel the need to reassure you that no snails are usually harmed in the making of this product, but I would recommend doing some research into each company's methods before investing

Get into it, yuh:

COSRX Advanced Snail 96 Mucin Power Essence

Mizon All In One Snail Repair Cream

Centella Asiatica

Known by names including but not limited to brahmi, asiatic pennywort, tiger grass and gotu kola; Centella Asiatica is a herb that has been traditionally used in Indian Ayurvedic medicine. The plant's leaves are sometimes used in salads and drinks. In K-beauty products, this hydrating skin-saver is predominantly used in moisturisers labelled 'cica creams'. U.S. brands from Estee Lauder have used it off and on in their formulations over the years—they just didn't call the products cica creams. Centella contains many active ingredients known as terpenoids. These terpenoids include asiatic acid, madecassic acid, asiaticoside and madecassoside. All four of which have been researched for their skincare benefits. Madecassoside serves as an antioxidant. There are other components in centella asiatica which have skincare benefits such as antioxidants, humectants and numerous vitamins.

With such impressive components, it's no surprise that centella is known and loved for its healing properties. A lot of centella asiatica containing products contain the prefix "cica" which, refers to the plant's cicatrising or healing/scar-forming abilities. Hence the existence of the cica creams we discussed earlier. The plant's healing abilities seem to be due to how it can speed up skin cell production and collagen synthesis. There is additional research showing it to be a rich source of amino acids which can help soothe upset or compromised skin whilst promoting hydration. Other studies have shown that centella asiatica containing products can help mitigate some of the visible effects of sun damage. That would largely be due to its antioxidant properties, a quality that may help prevent skin dulling to a certain degree by interrupting the negative processes caused by environmental stressors.

Get into it, yuh:

Bioderma Cicabio Repairing and Soothing Cream

La Roche-Posay Cicaplast Baume

Dr. Jart+ Cicapair Re-Cover Cream

Tranexamic Acid

A synthetic derivative of the amino acid lysine, this chemical is typically used to help treat heavy menstrual bleeding in women. Depending on intended use and results, it can be taken orally, injected into the lower skin layers [the dermis] or applied topically in the form of a cream or serum to help treat pigmentation disorders such as melasma and hyperpigmentation. Tranexamic acid can alter the way cells produce melanin – melanin being the pigment that gives skin its colour. The result is an interruption to the pathways that could otherwise lead to an uneven skin tone. Most of the evidence supporting the use of tranexamic acid in skincare products is regarding a reduction in dark spots and discolouration. In fact, in one study, it was found to have comparable results with hydroquinone but the participants who used tranexamic acid for 12 weeks reported higher satisfaction with their treatment, due to fewer side effects like skin irritation.

There was also a study where people who applied a 3% tranexamic acid treatment to their skin for 2 weeks showed fewer visible signs of rosacea than those who hadn't been using this treatment. Researchers from this study believe that the reduction in rosacea intensity is due to its action on blood vessels and a positive impact on skin barrier function. Unlike the evidence for tranexamic acid in pigmentation disorders, however, there have not been a lot of additional studies supporting its positive impact on the skin barrier's function.

This ingredient is safe for all skin types however those with eczema or established hypersensitivity to actives should make sure to patch test or start slowly with this ingredient. Common side effects include dryness, irritation and flaking with severe side effects being persistent skin discolouration, itching and swelling or hives.

Get into it, yuh:

Good Molecules Discolouration Correcting Serum

Peter Thomas Roth PRO Strength Niacinamide Discoloration Treatment

Murad Replenishing Multi-Acid Peel

the Inkey List Tranexamic Acid Night Treatment

Liquorice Root

The root of the liquorice plant has been used for medicinal purposes and confectionary for years, but it's also the source of a skincare game-changer. Liquorice root extract is used in skincare as a skin brightener. When applied topically, liquorice can do everything from being an antioxidant or anti-inflammatory to helping fade dark spots. Its action on pigmentation disorders is due to the inhibition of the production of an enzyme [tyrosinase] essential to the production of melanin. It also contains liquiritin, a compound that can help with the dispersion and removal of excess melanin in the skin. In other words, not only can it help prevent the formation of new spots, it assists in the fading of existing ones as well. As we all know, when it comes to fading spots, hydroquinone is the gold standard ingredient however there are numerous drawbacks to the use of this product including but not limited to general irritation. Liquorice root provides many of the same benefits with a lower chance of that irritation. With that in mind, however, this ingredient should not be used in conjunction with hydroquinone or retinol.

Like most plant-based extracts, liquorice contains a flavonoid, an antioxidant-rich component that decreases reactive oxygen species, which both age and discolour the skin. The generation of reactive oxygen species by UV radiation is one of the mechanisms through which UV light/ sun damage can be detrimental to skin health. Theoretically, liquorice root can help reverse some of the damage that the sun has done to the skin or potentially prevent further damage from occurring. While the flavonoid is anti-inflammatory in and of itself, there's yet another molecule, licochalcone A, which inhibits two inflammatory markers that trigger the inflammatory cascade.

Liquorice root is ideal for anyone looking to reap the spot-fading, skin tone evening benefits the ingredient has to offer as well as cashing in on those soothing benefits. It also serves as a wonderful alternative for those who cannot use hydroquinone either due to sensitivities, allergy or pregnancy.

Get into it, yuh:

TOPICALS Faded Brightening & Clearing Serum

Ole Henriksen Dewtopia™ 20% Acid Night Treatment

Peter Thomas Roth Goodbye Acne AHA/BHA Acne Clearing Gel

in case you wanna geek out

Healthline | Brainy Beauty: What Can PHAs Really Do for Your Skin?

allure | Your Guide to PHAs and Why They're Trending in Skin Care Right Now

Healthline | Try Bakuchiol, Retinol’s Gentle, Plant-Based Sister for Fresh, Healthy Skin

Paula’s Choice | Bakuchiol, what is it?

InStyle | Why So Many Skincare Products Have Mushrooms in Them Lately

Byrdie | Here's Everything You Need to Know About Snail Mucin

LAB MUFFIN BEAUTY SCIENCE | SKINCARE INGREDIENT SPOTLIGHT: CENTELLA ASIATICA

Mayo Clinic | Tranexamic Acid (Oral Route)

Healthline | Hoping to Even Out Your Skin Tone? Tranexamic Acid Could Help

LAB MUFFIN BEAUTY SCIENCE | TRANEXAMIC ACID: A NEWER SKINCARE INGREDIENT FOR PIGMENTATION

Byrdie | Tranexamic Acid Is the "It" Acid—Here's What You Should Know

PubMed | Ultraviolet Light Induced Generation of Reactive Oxygen Species

the JBeauty Collection | 5 Skincare benefits of licorice root extract (glycyrrhizinate)