Spirulina, a green-blue algae are prokaryotic and known to be the earliest form of life on earth. It is perhaps the most nutritious food in the world. Spirulina is very rich in dietary protein-about 65% of its composition is in dry form. Also, this superfood is the only source of a powerful antioxidant called phytocyanin, which means that it prevents cell oxidation and as a result aging.
You can stir a small spoon of Spirulina powder into a glass of water or juice and drink it straight or add to smoothies.