Dietary Supplement This special blue green algae (Spirulina platensis) is a low fat source of numerous vitamins, minerals, carotenoids, and essential fatty acids and an excellent source of many nutrients. Spirulina’s cell walls do not contain cellulose to slow down digestion. Spirulina supplies all nine essential amino acids including those containing sulfur. Source Naturals Spirulina Multiple combines spirulina with additional vitamins and minerals to provide a day’s worth of nutrients in just two tablets.