Algae, particularly species like Spirulina (a blue-green alga) and Chlorella, are used to support the treatment of anemia due to their high nutrient content—especially iron, which is essential for hemoglobin synthesis. Several scientific studies have evaluated the efficacy of algae supplementation in improving hemoglobin levels and alleviating iron-deficiency anemia. For example, research involving Spirulina supplementation in pregnant women and children has demonstrated improvements in hemoglobin concentrations and reductions in symptoms of anemia. The bioavailability of iron in algae is considered relatively high, and some studies suggest it may be better tolerated and absorbed than some conventional iron supplements.

In addition to iron, algae contain other nutrients such as vitamin B12 (though the bioactive form present is debated), folate, and proteins, all of which are important for healthy red blood cell production. However, while there is a growing body of evidence supporting the use of certain algae in anemia, most studies are small and of varying quality. Systematic reviews highlight positive trends but note the need for larger, well-controlled clinical trials to conclusively determine efficacy and safety, particularly in vulnerable populations.

Overall, the current scientific evidence offers moderate support for the use of algae, especially Spirulina, as a complementary approach to managing iron-deficiency anemia. It should not replace conventional treatments without medical supervision.