Epidemiological and clinical data suggest that dietary carotenoids such as astaxanthin may protect against cardiovascular disease (CVD) which includes hypertension. This condition is associated with blood vessel dysfunction, altered contractility and tone; mediated by relaxant (nitric oxide NO; prostacyclin) and constrictor factors (thromboxane; endothelin) in the blood. Furthermore, blood flow properties serve an important role in the pathological complications seen in atherosclerosis and coronary heart disease. Research presented here suggests that astaxanthin may be useful as part of an antioxidant therapy to alleviate hypertension.