Licorice root is used in Western products to add brightening and antioxidant properties to skincare products, but did you know that licorice root has been used in Korean skincare and medicine for centuries? Licorice root is one of the Korean Hanbang ingredients and it's an effective ingredient in relieving hyperpigmentation. What is the science behind licorice root and is it a truly functional ingredient in cosmetics?
The Science Behind Licorice Root
Licorice root extract or Glycyrrhiza glabra root extract is a perennial herb that grows in Central and Southwest Asia. Dried licorice roots are soaked in either water or alcohol, from which its active ingredients can then be filtered. Licorice root is harvested in the spring and autumn, and the plant must be old enough before it can be harvested annually. Cultivating it is therefore the result of a long process and effort.
Licorice root is used in medicine to treat many ailments and its healing effects are still being studied a lot. It has been found to have potential positive effects in the treatment of even serious diseases such as B- and C-Hepatitis. In Asian medicine, it is used e.g. in the treatment of coughs, asthma and rheumatism. Licorice root has been found to have antitumor, antiviral and anti-inflammatory effects. It has been used in skin care in Korea for hundreds of years. Several useful ingredients are obtained from licorice root, such as hundreds of different flavonoids that protect and strengthen the skin. The most important ingredients obtained from licorice root are glycyrrhizin, liquirit and glabridin. These are used in cosmetics to alleviate hyperpigmentation.
How does licorice root extract benefit skin?
The ingredients obtained from licorice root act as tyrosinase inhibitors. Tyrosinase is an enzyme found in the skin that forms pigment and is also the most significant factor in the formation of hyperpigmentation. Licorice root ingredients such as glabridin inhibit the activity of tyrosinase, which reduces the overproduction of pigment and thus prevents the formation of hyperpigmentation or melasma. Licorice root is rarely the only active ingredient in a product, but is often seen together with other tyrosinase inhibitors such as vitamin C and niacinamide.
Licorice root has been studied a lot and according to some studies, the glabridin obtained from it has been found to be up to 16 times more effective than hydroquinone in alleviating hyperpigmentation. (Hydroquinone is one of the most well-known and effective ingredients used for hyperpigmentation, but it is banned in the EU due to its potential carcinogenic nature.) In this study, in addition to licorice root, the test formulation also contained other hyperpigmentation-relieving ingredients, e.g. niacinamide and retinol, which accelerates skin regeneration.
Licorice root extract is an excellent ingredient for the treatment of hyperpigmentation because it also soothes the skin. When treating hyperpigmentation, it is important not to irritate the skin, as it can worsen the symptoms of hyperpigmentation. So licorice root does both, soothes the skin and prevents melanin overproduction. Therefore, it is an excellent addition to a formulation with potentially skin-irritating but effective active ingredients such as retinol.
Is licorice root extract safe?
No significant skin irritation has been observed with licorice root extract and it is generally a well-tolerated ingredient. In EU legislation, its use is not limited, but most of the time it is found in the product only in small concentrations. Licorice root is obtained from nature and some ethical concerns have been raised about its collection, since it is a very popular ingredient. Licorice is generally not recommended for pregnant women, so skincare products containing licorice root extract are also not recommended during pregnancy.
Products containing licorice root extract
Many Korean skincare products contain licorice root extract and most of these products are skin tone evening and brightening products. One of the most popular of these is Some By Mi Retinol Intense Reactivating Serum, which contains retinol, retinaldehyde, bakuchiol and licorice root extract. The Snail Truecica series from the same brand is also an excellent product series that enhances skin texture and evenness. Snail Truecica toner and serum are especially good for dry and sensitive skin with acne scars and/or hyperpigmentation. Skinfood's Yuja C Dark Spot Clear serum combines many skin tone-evening ingredients: niacinamide, vitamin C, tranexamic acid and licorice root extract.
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