Blue-green algae, of which spirulina is a well-known example, is a group of 1,500 species of microscopic aquatic plants. The two most common species used for human consumption are Spirulina maxima and Spirulina platensis. Spirulina is particularly rich in protein and also contains carotenoids, vitamins, minerals, and essential fatty acids.1
Spirulina’s vitamin B12 content does not appear to be readily usable by people.2 Most health benefits to humans claimed for spirulina and other blue-green algae supplementation are supported by anecdotes rather than scientific research. Test tube and animal studies have demonstrated several properties of large amounts of spirulina or spirulina extracts, including antioxidant,3 antiviral,4 5 anticancer,6 7 8 9 anti-allergy,10 11 immune-enhancing,12 13 14 liver-protecting,15 16 17 blood vessel-relaxing,18 and blood lipid-lowering19 20 effects.
