Ergothioneine

Ergothioneine is an unusual amino-acid antioxidant that human cells actively import via a dedicated transporter (OCTN1) — biology’s own proof of its value. Concentrated in high-oxidative-stress tissues, it accumulates in skin cells where it scavenges radicals, chelates iron, and protects mitochondria from UV and pollution damage. Research shows reduced post-UV inflammation and support of cellular repair at 0.01–0.05%. Unstable elsewhere, it is exceptionally stable in skin. Premium "urban protection" and blue-light serums increasingly feature it. Think of it as an intracellular bodyguard: unlike surface antioxidants, ergothioneine works inside the cell where damage actually begins.