Astaxanthin is an antioxidant (a substance that inhibits oxidation) & is a carotenoid. Astaxanthin therefore protects cells from damage & improves the way the immune system functions. Astaxanthin has also been used in the treatment of Alzheimer's disease Parkinson's disease strokes high cholesterol & AMD (Age Related Macular Degeneration). It is also suggested it may be used for reducing the risk of certain cancers. Naturally found in small quantities in salmon trout krill & the feathers of some birds. It provides the red colour of salmon meat & cooked shellfish.