Spirulina is a type of algae that is very high in protein and nutrients. When cultivated properly, it is one of the most potent nutrient sources available. Since spirulina has a high amount of proteins and amino acids, it is very useful to vegetarians and vegans. High iron content along with protein also make spirulina a good food source when pregnant, recovering from surgery, or whenever your immune system needs a boost. This green super food is also very high in chlorophyll.