Spirulina is a tiny aquatic plant that has been eaten by humans since prehistoric times. It is a simple, one-celled form of algae that thrives in warm, alkaline fresh-water bodies. It’s blue-green in color that is rich in protein, vitamins, minerals, and carotenoids (a type of antioxidant that can help protect cells from damage) than other known natural vegetable such as soy and carrots...etc. The name "spirulina" is derived from the Latin word for "helix" or "spiral"; denoting the physical configuration of the organism when it forms swirling, microscopic strands. It was discovered in South American and Africa in natural alkaline lakes. Spirulina is known to exist 3.5 billion years ago.

Spirulina is the common name for human and animal food supplements similar to Chlorella and Aphanizomenon flos-aquae (Blue Green Algae.) Spirulina is extraordinary rich in micronutrients, which are easily absorbed by humans because it does not have any cellulosic wall. Spirulina is rich in beta-caroten (from which vitamin A is made), iron, vitamin B12, ganna-linolenic acid and other essential fatty acids, and other essential micronutrients.

Spirulina comes from two different species of cyanobacteria: Arthrospira platensis, and Arthrospira maxima. These and other Arthrospira species were once classified in the genus Spirulina. There is now agreement that they are a distinct genus, and that the food species belong to Arthrospira; nonetheless, the older term Spirulina remains the popular name. Spirulina is cultivated around the world, and is used as a human dietary supplement as well as a whole food and is available in tablet, flake, and powder form. It is also used as a feed supplement in the aquaculture, aquarium, and poultry industries.

Spirulina is being developed as the "food of the future" because of its amazing ability to synthesize high-quality concentrated food more efficiently than any other algae. Spirulina is rich in protein which is a core substance of any life forms, and the constituent amino acids thereof are ideally balanced. It is now being widely studied for its possible antiviral, anticancer, antibacterial, and antiparasitic properties, and has been used for such medical conditions as allergies, ulcers, anemia, heavy-metal poisoning, and radiation poisoning. It is also used in weight-loss programs.

Depending on the growing conditions, spirulina can be as much as 70% protein, and the protein is complete, rather than partial, as is the case with most proteins of plant origin. Spirulina also contains vitamins and nutrients like iron, calcium, vitamin B, magnesium, zinc, and beta carotene, among others. However, one must eat a significant serving of spirulina each day to really benefit from its nutritional value, rather than having a small sprinkle now and then.