Quercetin

What is it?

A flavonoid antioxidant found in many fruits and vegetables, studied in skincare for photoprotective and anti-aging properties.

What does it do?

According to PubMed, a study developing a quercetin nano-emulsion for topical delivery found it significantly reduced UVA-induced photoaging markers in both human skin fibroblasts and a mouse model -- 73% reduction in senescence-associated markers, 66% reduction in reactive oxygen species, and a 30.6% reduction in UVA-induced skin-fold thickening in vivo, via modulation of the NRF2/NF-kB signaling pathway -- real mechanistic and in vivo evidence supporting quercetin as a photoprotective active once delivery challenges (poor solubility, low skin permeability) are addressed via formulation.

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