[(Spirulina)https://anadey.com.au/search?query=Spirulina] (arthrospira) is a blue-green algae found in alkaline ponds around the world. It does not have a hard cell wall making it harder to digest, but a soft, easily digested cell wall made of a [(mucopolysaccharide)https://anadey.com.au/search?query=mucopolysaccharide]. Spirulina is a non nitrogen-fixing blue-green alga, which makes it safe for human consumption. In fact, it has undergone 30 years of safety testing with excellent results. However, spirulina has been around and has been consumed by humans for thousands of years.