One thing that is constant in Korean Skincare is its ever-growing innovation. People also love the fact that they utilise game-changing natural ingredients in skincare products that work wonders for our skin, from snail mucin, mugwort, bamboo extract, Centella Asiatica—the list goes on. Recently, a new, highly desired ingredient is on top of the K-Beauty trend. Can you guess what it is? Please give a big round of applause to our promising newcomer, Houttuynia cordata. This ingredient has been gaining in popularity and incorporated in many skin care products like cleansers, toners, serums, essences, creams, sheet masks, spot treatments—you name it. Let's find out why the beauty community is raving about it!

What is Houttuynia Cordata?

Houttuynia cordata—also known as Heartleaf, Fish Mint, Fish Leaf, Fish Wort, Chameleon Plant, Chinese Lizard Tail, Bishop's Weed, or Rainbow Plant—belongs to the family of Saururaceae. In Korean, it is commonly called 어성초 (eoseongcho) for its awful fishy scent or 십약 (sipyak) which literally translates to 'ten medicines' since it can be used to alleviate various ailments. Japanese recognises this plant as 蕺草 (dokudami), but just like in Korean, it also has an affectionate nickname with the meaning of 'ten medicines', 十薬(jūyaku). Despite its distinct odour, Houttuynia cordata is visually attractive. Its heart-shaped green leaves are elegantly framed with yellow and red hues, hence its many nicknames. This herbaceous perennial herb grows in moist, shady locations in Asian countries, including Southeast Asia, Northeast India, Korea, Japan, China, and others.

Health benefits

Long before it was used as an ingredient in our skincare products, people all across Asia consumed its leaves, stems and roots as food and beverages. Even today, they still serve it for culinary purposes. For instance, in India, China and Vietnam, Houttuynia cordata is eaten raw as salad or cooked with other vegetables, fish, or meat. Meanwhile, in Japan and Korea, people use its dried leaves to brew herbal tea. While the pungent taste of Houttuynia cordata may not be for everyone, there's no doubt that it possesses incredible health benefits. I mean, just by reading its nicknames, we can at least have that many expectations, right?

This native Asian plant is valued for its medicinal properties and used internally to treat cholera, dysentery, high blood sugar, high blood pressure, blood deficiency, coughs, fever, indigestion and constipation. Externally, Houttuynia cordata is used to treat snake bites and skin disorders.

Skin benefits

The main bioactive compound that has been isolated from Houttuynia cordata is called flavonoids—a family of polyphenolic compounds in plants. Some of the flavonoids found within this particular plant are Quercetin, Quercitrin, Hyperoside, Rutin, Afzelin, and Apigenin. These polyphenolic flavonoids are efficient antioxidants that scavenge oxygen radicals and possess anti-inflammatory properties.

Besides the active components mentioned above, Houttuynia cordata also contains polysaccharides—large molecules of various sugar units, including galacturonic acid, galactose, arabinose, glucuronic acid, etc. In skincare products, polysaccharides work as humectants, meaning they attract water to and hold it in the skin, moisturising the skin and helping it maintains its softness and elasticity. Supplementary to their hydrating nature, they also exhibit excellent antioxidant effects by being free radical scavengers.

Antioxidant

Houttuynia cordata is an excellent source of natural antioxidants. Besides having a high content of polyphenolic flavonoids, it is also rich in polysaccharides, amino acids and fatty acids, which possess powerful antioxidant properties. They are very helpful in fighting off and neutralising circulating free radicals from air pollution, UV rays, smoke, lack of sleep, poor diet, alcohol, stress, etc.

Facial skin is the most UV exposed area. Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to the skin, resulting in sunburn, erythema, skin inflammation, pigmentation, dehydration, skin ageing, skin cancer and more. UV irradiation stimulates the production of reactive oxygen species (ROS) that could damage our skin cells. Based on a research, Quercitrin shows a protective effect on the skin by decreasing ROS generation from UVB exposure.

Furthermore, as you may already know, antioxidants play an essential role in diminishing the appearance of wrinkles and fine lines. Even though topical application of antioxidants in skincare may provide a shield against free radicals from causing more damage to the skin, it is better to set our expectation straight by realising that it won't make us look 15 years younger.

Librarian Tip: Combine Houttuynia Cordata with ingredients like Ceramides, Glycerin, Hyaluronic Acid, Retinol and Niacinamide for better results in the attempt of "looking young". Also, never forget to wear your sunscreen rated SPF 30 or greater.

Antibacterial and anti-inflammatory

One of the many reasons people with acne-prone skin love this ingredient is its antibacterial properties. Houttuynia Cordata extract has a strong antimicrobial effect against bacteria most commonly contributed to acne, Propionibacterium acnes and Staphylococcus epidermidis.

These acne-causing bacteria stimulate pro-inflammatory mediators or cytokines to initiate the inflammatory process that results in the emergence of acne on the skin. Luckily, we can prevent it from happening with a little bit of help from Houttuynia cordata extract. According to a study, this powerful ingredient effectively reduces pro-inflammatory mediators' production. In other words, it can be beneficial in the treatment of acne vulgaris. However, further studies are needed to know whether it helps inhibit the cytokines mechanism. On the flip side, great news for all acne-prone skin type, a recent study published in 2019 has concluded that mild to moderate inflammatory acne lesions significantly reduced by eight weeks of applying this herbal extract.

Similarly, Houttuynia cordata also exhibits a distinguished outcome in treating atopic dermatitis (AD) or eczema—a chronic inflammation of the skin that typically affects the face, neck, arms and legs. Staphylococcus aureus has been proposed to be one of the bacteria inducing AD. The strong anti-inflammatory activity of Houttuynia cordata inhibits pro-inflammatory cytokines and relieves AD inflammation.

In a nutshell, Houttuynia cordata makes a great ingredient to calm and soothe red, irritated or inflamed skin.

Brightening

Melanin is a major pigment responsible for the colour of the skin. Sun exposure and inflammation (i.e. acne) result in the overproduction of melanin. Consequently, hyperpigmentation—such as melasma, sunspots, and post-inflammatory hyperpigmentation—may occur. Some of the culprits to this unfortunate event are free radicals and tyrosinase. Antioxidants aid in preventing or delaying pigmentation by battling the free radicals, therefore obstructing melanin synthesis. Not to mention, high phenolic content in Houttuynia cordata hinders tyrosinase activity. That's how this ingredient got its ability to brighten the complexion.

Houttuynia cordata in skincare products

These days, you can find Houttuynia cordata in almost every skincare products available in the market. If you are wondering which ones of those products enable you to reap all the amazing benefits of the ingredient, of course, it will come down to whichever sits on the skin for a longer time to allow the product to deliver its maximum potential, for instance, serums, essences, and creams. Anyone with any skin type can benefit from this plant extract, especially those with acne-prone and sensitive skins.

Considering its many benefits and how gentle it is on the skin, it is safe to say that Houttuynia cordata can be used in the morning and evening daily. A few studies confirm that generally, it does not show any toxic effect or adverse reaction. That being said, just like any plant extracts, which is a complex mixture of many chemical compounds, extraction methods, preparations, and the concentration of active ingredients, to mention a few, require special attention. Scientific studies focused on developing formulations for topical application are needed to ensure its safety and efficacy.

If you are interested in trying Houttuynia cordata, it may be worth patch-testing first to see if you react negatively to it. Or you can always check in with a dermatologist if you have questions regarding your skin concerns.

Lastly, if you are wondering whether or not Houttuynia cordata resembles Centella Asiatica: actually, they do. Most plant extracts share similarities in terms of skin benefits. Generally, plant-derived products are rich in vitamins, antioxidants, and bioactive extracts or phytochemicals. Even though Houttuynia cordata and Centella Asiatica come from different families, both have equally great antioxidant, antimicrobial and anti-inflammatory properties that are suitable for all skin types, especially acne-prone and sensitive skin types. In my opinion, it is unnecessary to compare them; what's more important is to pick a product with ingredients that works better and feels more comfortable on your skin since skincare is something very personal that is different for each individual.

Product recommendations

BEAUTY OF JOSEON Green Plum Refreshing Cleanser

Suitable for: All Skin Types

A mild gel cleanser which effectively cleanses skin without stripping it of its natural moisture barrier. Take an appropriate amount of the pale green coloured gel and massage it into the skin to remove excess sebum and dirt without worrying about tugging at the skin. Rinse off with lukewarm water to leave cleansed and supple skin.