Spirulina, a blue-green algae rich in proteins, vitamins, minerals, and antioxidants, has been explored as a supportive supplement during chemotherapy, primarily to reduce side effects such as immunosuppression, anemia, and oxidative stress. Several animal studies and a limited number of small clinical trials suggest that spirulina may help mitigate some of the adverse effects associated with chemotherapy. For example, spirulina’s antioxidant components—particularly phycocyanin—can help reduce oxidative damage induced by chemotherapeutic agents. Additionally, spirulina has shown immunomodulatory effects, potentially supporting white blood cell counts and improving immune function, which can be compromised during chemotherapy.

Some clinical studies in humans, though generally small and preliminary, have reported improvements in hemoglobin levels, reduced incidence of chemotherapy-induced anemia, and better overall tolerance to chemotherapy regimens when spirulina is used as an adjunct. However, these studies often lack large sample sizes, robust controls, or consistent dosing, limiting the strength of their conclusions.

In summary, while there is emerging scientific evidence suggesting that spirulina may help reduce some chemotherapy side effects, the data is not yet strong or comprehensive enough for broad clinical recommendations. More rigorous, large-scale human studies are needed to confirm these effects and establish optimal dosing and safety. Therefore, spirulina’s use in this context is best described as having scientific interest and some preliminary support, but evidence quality remains modest.