Spirulina is an algae, and one of the most complete foods on the planet. It is well known for its huge antioxidant content, but is also a rich source of protein. This protein is abundant in all nine of the essential amino acids (those we cannot make for ourselves and so have to obtain from food). Spirulina also provides several highly-concentrated vitamins and minerals. Centuries ago the Aztec civilisation cultivated it as a staple food, and today it is regarded as central to some Asian diets. Although it can grow in natural conditions, most Spirulina today is produced commercially. Spirulina replicates itself by photosynthesis, extracting energy from light. The product of this is chlorophyll, the substance that makes plants green. In nutrition terms however, chlorophyll is exceptionally useful. It is a significant aid to the absorption of many vitamins and minerals, it is antioxidant and it aids the growth and repair of tissue. Another pigment in Spirulina is Phycocyanin, which is believed to help optimise blood health and is antioxidant. The protein content of Spirulina makes it popular with people following fitness regimes. Of equal value is the vitamins it provides. It is rich in Vitamin A, which aids our reproductive systems, is required by our retinas and is essential for basic body maintenance. It has more Vitamin B1 than cows" milk, required for proper function of the nervous system and muscles. Its Vitamin B2 helps us extract energy from carbohydrates and produce healthy red blood cells. Vitamin B6 is required for the absorption of amino acids and chemicals involved in brain function. It also helps muscle function, enabling blood haemoglobin to bind oxygen. B9 (folic acid) is essential for women before and during pregnancy, as well as being beneficial to blood health. Vitamin C helps heal wounds and regulate blood flow, but is also highly antioxidant.