This is a summary of research papers and studies
from the National Center for Biotechnology Information (NCBI)
ABOUT LICORICE ROOT EXTRACT
Licorice root, scientifically known as Glycyrrhiza glabra, Glycyrrhiza uralensis, and Glycyrrhiza inflata, is a perennial herb with a rich history of use spanning ancient Assyrian, Egyptian, Greek, Chinese, and Indian cultures. Often referred to as "sweet root" or "gan cao," it has traditionally been employed for conditions ranging from respiratory ailments to wound healing. In the modern era, licorice root extract has emerged as a powerhouse ingredient in dermatological science, valued for its complex chemical profile and multifaceted benefits for the skin.
Properties
The therapeutic efficacy of licorice root is derived from its diverse array of bioactive natural products. The primary components responsible for its biological activities include saponins, flavonoids, coumarins, and triterpenoids. One of the most significant constituents is glycyrrhizin (or glycyrrhizic acid), a major component used as a remedy for inflammation and allergies. Other critical bioactive molecules found in the extract include glabridin, isoliquiritigenin, and liquiritoside.
Functions and Skin Benefits
Licorice root extract functions through several biological pathways to improve skin health. Its primary roles include anti-inflammatory action, skin brightening, anti-aging, and moisturization.
Skin Brightening and Hyperpigmentation
One of the most celebrated functions of licorice root extract is its ability to brighten the skin and even out skin tone. It achieves this by acting as a natural tyrosinase inhibitor. Tyrosinase is a key enzyme in the production of melanin; by inhibiting its activity, licorice extract reduces melanin synthesis, thereby addressing dark spots, sun damage, and uneven pigmentation. Studies specifically highlight that components like glabridin and isoliquiritigenin contribute to this potent tyrosinase inhibitory activity, making it a popular alternative to synthetic skin-brightening agents.
Anti-Inflammatory and Soothing Properties
Licorice root extract is highly effective in soothing and calming irritated skin, which is particularly beneficial for sensitive skin types or conditions like eczema and rosacea. Its anti-inflammatory activity is often compared to the action of hydrocortisone. This is due to its ability to inhibit phospholipase A2, an enzyme critical to various inflammatory processes, as well as cyclooxygenase activity and prostaglandin formation (specifically PGE2). Clinical evidence suggests that topical gels containing licorice can significantly reduce symptoms of atopic dermatitis and aid in burn healing by calming the skin’s inflammatory response.
Anti-Aging and Photoprotection
The extract provides substantial anti-aging benefits by protecting the skin from environmental stressors such as UV radiation and pollution. It inhibits elastase activity, the enzyme responsible for breaking down elastin, thereby helping to maintain skin firmness and elasticity. Furthermore, its antioxidant properties help neutralize free radicals that lead to premature aging and the formation of fine lines and wrinkles. By shielding the skin from oxidative stress, licorice extract preserves the skin’s structural integrity over time.
Moisterization and Acne Support
Acting as a natural humectant, licorice root extract attracts and retains moisture within the skin, improving overall hydration and plumpness. Beyond hydration, it possesses antibacterial properties that can reduce the growth of acne-causing bacteria. It also helps in reducing the appearance of blemishes, making it a versatile ingredient for both dry and acne-prone skin types.
Safety
While licorice root is generally considered safe for topical use in the short term, there are important safety considerations to keep in mind.
- Topical Safety: Topical application is usually well-tolerated, though it may cause skin irritation in some individuals.
- Systemic Concerns: Oral consumption of licorice containing glycyrrhizin can lead to serious side effects, such as hypertension, irregular heartbeat, and cardiac arrest, especially in large amounts or for individuals with heart or kidney conditions.
Conclusion
Licorice root extract is a versatile and potent botanical ingredient with a wide array of dermatological applications. Its ability to brighten skin, inhibit inflammation, and provide antioxidant protection makes it an invaluable component of modern skincare.