Astaxanthin is a potent carotenoid antioxidant found in marine algae, red yeast and many other plant and animal sources. Animal studies indicate that it reduces blood glucose and ameliorates several parameters of the diabetic metabolic syndrome.

It improves blood flow and vascular tone in models of hypertension. In vitro studies indicate that it upregulates connexin 43 and thus, may be chemopreventive against cancer.