Quercetin

It is a highly potent, biologically active flavonoid that occurs naturally in citrus fruits, for example. Our product contains a highly concentrated quercetin extract from the Sophora japonica tree. Quercetin is a powerful antioxidant with anti-inflammatory properties that protects cell structures and blood vessels from the harmful effects of free radicals. It strengthens blood vessels. Its antioxidant properties are difficult to stabilise because it oxidises rapidly. Our innovative form of quercetin remains highly effective because it is stabilised and gently incorporated into our formulations. In in vitro and clinical studies, Quercetin has demonstrated the ability to inhibit basophil degranulation, i.e. to reduce allergic skin problems and boost the skin's own antioxidant defences. Clinical studies have shown that it helps with various types of skin concerns, providing relief and first aid for irritated skin. This flavonoid belongs to the group of polyphenols that plants produce to protect themselves against oxidative stress, UV radiation and pathogens. Sophora japonica bark extract contains up to 98 % pure quercetin, making it an ideal source for cosmetic applications. Unlike synthetic antioxidants, it offers natural synergy with other phytochemicals, enhancing overall skin protection.

Quercetin acts as a powerful antioxidant by neutralising free radicals and reducing oxidative stress in skin cells. It inhibits enzymes responsible for inflammation, such as COX-2, helping to soothe irritation and redness. It supports skin barrier repair by protecting lipids from peroxidation and increasing collagen synthesis. It has anti-inflammatory and anti-allergic effects by blocking the release of histamine from mast cells. In cosmetics, a concentration of 0,5 to 2 % is recommended in serums, creams and masks for optimal stability and effectiveness without irritation.

It is particularly recommended for sensitive, irritated, dry and mature skin, where it reduces inflammation and strengthens the skin barrier. Its anti-inflammatory properties also make it suitable for skin prone to acne or rosacea, as well as dehydrated skin, where it improves hydration. It is not recommended for extremely sensitive skin without a patch test first, as it may cause sensitisation in rare cases.

A study published in the Journal of Investigative Dermatology (2018) demonstrated that quercetin applied topically at a concentration of 1 % reduced the expression of the pro-inflammatory cytokines IL-6 and TNF-α by 45 % in patients with atopic dermatitis after 4 weeks. Another clinical study in the International Journal of Molecular Sciences (2021) showed that quercetin inhibits melanogenesis by 32 % at a concentration of 0,5 % in vitro, thereby reducing hyperpigmentation. These results confirm its specific benefits for skin inflammation and ageing.