Astaxanthin is a carotenoid naturally present in some algae and which gives their typical color to fish such as salmon and crustaceans such as lobster and shrimp. Astaxanthin is endowed with antioxidant power: it is therefore attributed the ability to protect cells from damage associated with oxidation. It is also believed to improve the functioning of the immune system. Its intake is proposed in the treatment of Alzheimer’s disease, Parkinson’s, stroke, high cholesterol and age-related macular degeneration. It is also used for cancer prevention and, applied directly to the skin, to protect the skin from sunburn.