Spirulina supplementation has been shown in a variety of populations to improve markers of iron deficiency anemia, including increased levels of hemoglobin, a higher red blood cell count, and an increased hematocrit.[1][2][3][4][5]
This effect could relate to spirulina’s highly bioavailable iron (although there are only ~5 mg of iron per 10 grams of dried spirulina),[6] but the predominant protein in spirulina, phycocyanin, may also stimulate red blood cell production.[7]
There currently isn’t enough research to suggest that spirulina might be a replacement for standard anemia treatments such as iron supplementation. Additionally, the nutritional content of spirulina can vary depending on the cultivation and processing techniques used, which could alter its effectiveness for anemia.[8]