The positive effects of Spirulina in allergic rhinitis are based on adequate evidence but larger trials are required. It is believed that the anticancer effects of Spirulina are perhaps derived from β-carotene, a known antioxidant; however, the link between β-carotene level and carcinogenesis cannot be established as the etiology of carcinoma is frequently multifactorial [26, 27]. There are some positive studies on the cholesterol-lowering effects of Spirulina but larger studies are required before any definitive conclusions can be made. Finally, there are no high-level evidence trials on the role played by Spirulina in chronic fatigue and in antiviral applications. At the moment, what the literature suggests is that Spirulina is a safe food supplement without significant side-effects but its role as a drug remains to be seen.