astaxanthin is a natural red carotenoid pigment and a powerful antioxidant , it gives the red or pink colour to salmon, shrimp, krill and flamingos, is a fat-soluble xanthophyll carotenoid widely recognized as one of the most powerful natural antioxidants on Earth—boasting up to 6,000 times the free-radical quenching capacity of Vitamin C. Its unique molecular shape spans across the entire lipid bilayer of cell membranes, providing absolute internal and external protection without ever turning into a pro-oxidant.