Spirulina Scientific References and Clinical Study Library

Spirulina scientific references are scattered across hundreds of papers of very uneven quality, which makes it hard to tell a solid trial from a promotional claim. This library gathers the key human, safety and laboratory studies in one place, sorted by study type so you can see how strong each kind of evidence is. Every entry lists its design, population and dose, and links to PubMed or an official source. Use it to check a claim, plan a literature review or judge a product's evidence for yourself.

How this library of spirulina scientific references is organized

Evidence is arranged from the strongest design to the weakest, so you can see how much weight each source deserves. Systematic reviews and meta-analyses come first, then randomized trials, then uncontrolled human studies. Pharmacokinetic, safety, mechanistic and preclinical sources follow, and a summary table and link list close the page.

What is included. Each entry was checked against its PubMed record, publisher page or official government source during compilation in October 2026. Where no PubMed ID was confirmed, the entry links to a PubMed title search and no identifier is given. Details taken only from secondary summaries are marked as such.

How to read it. A study listed here is not an endorsement of its result. Most spirulina trials are small and short, use different products, and report surrogate markers. See the Complete Scientific Guide to Spirulina for interpretation and evidence grades.

Medical disclaimer: this library is for education and does not diagnose, treat or prevent any condition. Talk to a qualified healthcare professional before using spirulina, especially if you are pregnant, have an autoimmune condition, take immunosuppressants or have a metabolic disorder.

Spirulina systematic and narrative reviews

These reviews summarize the literature without pooling trial data, or review case reports.

• Karkos PD, Leong SC, Karkos CD, Sivaji N, Assimakopoulos DA (2011). Spirulina in clinical practice: evidence-based human applications. Evid Based Complement Alternat Med 2011:531053. A narrative review of mechanisms, applications, safety and levels of evidence. PubMed 18955364 · DOI · PMC
• Mysliwa-Kurdziel B, Solymosi K (2017). Phycobilins and phycobiliproteins used in food industry and medicine. Mini Rev Med Chem 17(13):1173–1193. Reviews stability, bioavailability and safety of phycocyanin pigments. DOI
• Carvalho JF, Martinez ATA (2025). Spirulina ingestion and autoimmune disease onset or flare. Adv Rheumatol. Reviews published case reports and concludes that patients with autoimmune disease should watch for flares. DOI
• Weiner JD, Hill A, Shen C, On A, Werth VP (2025). Identifying immunostimulatory herbal supplements that may flare autoimmune skin diseases: a systematic scoping review. Lupus Sci Med. Citation taken from a secondary summary; confirm details in the journal.

Spirulina meta-analyses

Pooled analyses of randomized trials give the most reliable human estimates, but they combine small and varied studies.

• Serban MC et al. (2016). Meta-analysis of 7 RCTs on plasma lipids. Clin Nutr 35(4):842–851. Reported lower total cholesterol (−46.76 mg/dL), LDL-C (−41.32 mg/dL) and triglycerides (−44.23 mg/dL), and higher HDL-C (+6.06 mg/dL). PubMed 26433766 · DOI
• Huang H, Liao D, Pu R, Cui Y (2018). Effects of spirulina on lipids, glucose, body weight and blood pressure. Diabetes Metab Syndr Obes 11:729–742. 12 trials (14 arms), 1–19 g/day, 2–48 weeks; favourable effects on lipids, glucose and diastolic pressure. PubMed 30532573 · DOI
• Machowiec P et al. (2021). Spirulina and systolic and diastolic blood pressure. Nutrients 13(9):3054. 5 RCTs, 230 participants; lower blood pressure, with calls for larger trials. First author per a secondary source. Full text · PMC
• Hatami E et al. (2021). Spirulina in type 2 diabetes. J Diabetes Metab Disord 20(1):883–892. 8 studies; fasting glucose fell by about 17.9 mg/dL, with no significant effect on HbA1c or postprandial glucose. First author per a secondary source. PMC
• Bohórquez-Medina SL et al. (2021). Spirulina in obesity-related metabolic disorders. 7 RCTs (n = 338); triglycerides and total cholesterol fell, while LDL-C, fasting glucose and HbA1c did not change significantly. Record
• GRADE-assessed dose-response meta-analysis on lipid profile (2023). Pharmacol Res. Searched to January 2023 and reported improved TC, TG, LDL-C and HDL-C. PDF
• Spirulina alone or with exercise in overweight and obese adults (2025). Front Nutr, PROSPERO CRD42024573534. DOI · PMC

Note: the 2016 lipid effects are large relative to the 2021 pooled estimates, which found no LDL-C change. This difference is an example of why conclusions depend on which trials are pooled.

Spirulina randomized controlled trials

Trial size is the main limit: most enrolled fewer than 150 people.

• Parikh P, Mani U, Iyer U (2001). 25 adults with type 2 diabetes; 2 g/day for 2 months versus a control group; lower fasting and postprandial glucose, HbA1c and triglycerides. J Med Food 4(4):193–199. PubMed 12639401 · DOI
• Mao TK, Van de Water J, Gershwin ME (2005). Allergic rhinitis patients fed 1 or 2 g/day; lower IL-4 production from stimulated blood cells. J Med Food 8(1):27–30. PubMed 15857205 · DOI
• Lu HK et al. (2006). 16 untrained students for 3 weeks; lower malondialdehyde and longer time to exhaustion. Eur J Appl Physiol 98(2):220–226. PubMed 16944194 · DOI
• Cingi C, Conk-Dalay M, Cakli H, Bal C (2008). Double-blind, placebo-controlled; 150 patients enrolled; symptom scores improved with spirulina (P < 0.001). Dose of 2 g/day and 129 completers come from a secondary summary. Eur Arch Otorhinolaryngol 265(10):1219–1223. PubMed 18343939 · DOI
• Kalafati M et al. (2010). 6 g/day for 4 weeks versus placebo; time to fatigue rose and fat oxidation rose 10.9%. Med Sci Sports Exerc 42(1):142–151. PubMed 20010119 · DOI
• Nourollahian M et al. (2020). Spirulina platensis versus cetirizine in allergic rhinitis. Acta Otorhinolaryngol Ital. Listed in a secondary source; search PubMed.
• Pappas A et al. (2021). 24 recreationally trained men; 6 g/day; no benefit on redox status, muscle performance or damage after eccentric exercise. A null result. Int J Mol Sci 22(7):3559. DOI
• Elite rugby players (2022). 17 players; 5.7 g/day for 7 weeks; smaller rises in lipid peroxidation, CRP and creatine kinase after exhaustive exercise. PubMed 35394687
• Registered trial: NCT02837666, spirulina and exercise on lipids and antioxidant capacity.

Observational and uncontrolled human studies of spirulina

Studies without a control group cannot separate the supplement from time, diet or regression to the mean.

• Mazokopakis EE et al. (2014). 52 Cretan outpatients with dyslipidaemia took 1 g/day for 12 weeks with no placebo group; total cholesterol, LDL-C and triglycerides fell. J Sci Food Agric 94(3):432–437. Search PubMed
• Mazokopakis EE et al. (2014). Pilot study in 15 adults with non-alcoholic fatty liver disease; 6 g/day for 6 months; weight fell 8.1% and HOMA-IR 19.6%, with no change on ultrasound. Ann Gastroenterol 27(4):387–394. PMC4188938
• Selmi C et al. (2011). 40 volunteers aged 50 or older with a history of anemia, 30 completing 12 weeks; mean corpuscular hemoglobin and IDO activity rose. Cell Mol Immunol 8(3):248–254. PMC4012879
• Hirahashi T et al. (2002). Healthy volunteers given a hot-water extract (50 mL); NK-cell interferon-γ production and cytolysis rose in more than half of subjects. Int Immunopharmacol 2(4):423–434. PubMed 11962722

Spirulina pharmacokinetic and bioavailability studies

No validated human pharmacokinetic study of oral spirulina pigments was found. The sources below describe digestion, binding and nutrient bioavailability, and they do not show how much phycocyanin or phycocyanobilin reaches human blood.

• Minić S (2021). The bioactive properties of Spirulina-derived phycobiliproteins and phycobilins. Biologia Serbica. Reviews bioavailability, distribution and chromopeptides formed in simulated digestion. Journal page
• Digestion by pepsin releases biologically active chromopeptides from C-phycocyanin. Laboratory digestion study; activity is linked to the chromophore. Record
• Phycocyanobilin binding to human serum albumin (2015). RSC Adv. Experimental and modelling data that phycocyanobilin binds albumin sites also used by bilirubin. Publisher PDF
• Watanabe F et al. (1999). Pseudovitamin B12 is the predominant cobamide of spirulina tablets: 83% pseudovitamin B12 and 17% vitamin B12 among intrinsic-factor-active analogues. J Agric Food Chem 47(11):4736–4741. PubMed 10552882 · DOI

Spirulina safety and toxicology studies

• Marles RJ et al. (2011). United States Pharmacopeia safety evaluation. Reviewed trials, animal data and 31 adverse event reports, and assigned a Class A safety rating to Spirulina maxima and S. platensis. Crit Rev Food Sci Nutr 51(7):593–604. PubMed 21793723 · DOI
• Gilroy DJ et al. (2000). Microcystin in blue-green algae supplements; Oregon set a 1 µg/g limit. The products were mainly Aphanizomenon-based, not spirulina. Environ Health Perspect 108(5):435–439. PubMed 10811570 · DOI
• Lee AN, Werth VP (2004). Three patients whose pemphigus vulgaris or dermatomyositis began or flared after immunostimulatory supplements, including spirulina. Arch Dermatol 140(6):723–727. PubMed 15210464 · DOI
• Mazokopakis EE et al. (2008). Case report of acute rhabdomyolysis with spirulina. Phytomedicine. Search PubMed
• Hutadilok-Towatana N et al. (2008). 12-week feeding of fresh or dried S. platensis in rats; no effects on behaviour, growth or clinical chemistry. Food Sci Technol Res 14(4):351. Journal page
• LiverTox: Spirulina. Clinically apparent liver injury is described as rare. NBK548312
• LactMed: Spirulina. No data on use during breastfeeding. NBK501849

Mechanistic studies of spirulina

These papers propose how spirulina components act. Most are hypotheses or laboratory findings.

• McCarty MF (2007). Hypothesis that phycocyanobilin inhibits NADPH oxidase, in the manner of bilirubin. The author estimated that about 15 g of spirulina could supply roughly 100 mg of phycocyanobilin, and he later declared a patent interest in related products. J Med Food 10(4):566–570. PubMed 18158824
• Pentón-Rol G, Marín-Prida J, McCarty MF (2021). Review of C-phycocyanin-derived phycocyanobilin in neurodegenerative disorders. Curr Neuropharmacol 19(12):2250–2275. DOI
• Hayashi T et al. (1996). Calcium spirulan, a sulfated polysaccharide that inhibited several enveloped viruses in cell culture by blocking viral penetration. J Nat Prod. PubMed 8984158
• Lee JB et al. (2001). Metal-ion and depolymerization effects on spirulan activity against herpes simplex virus type 1. Chem Pharm Bull 49(1):108–110. J-STAGE
• Pancreatic lipase inhibition (2006). An aqueous extract, a glycolipid and phycocyanin inhibited the enzyme and lowered postprandial triglycerides in rats. Yakugaku Zasshi 126(1):43–49. PubMed 16394649

Preclinical studies of spirulina

Animal and cell studies often use isolated pigments or doses that exceed realistic human intake, so their results should not be read as human outcomes.

• Riss J et al. (2007). Hamsters on an atherogenic diet; phycocyanin reduced oxidative stress, NADPH oxidase expression and aortic fatty streaks. J Agric Food Chem 55(19):7962–7967. PubMed 17696484 · DOI
• Nagaoka S et al. (2005). C-phycocyanin as a key component of the cholesterol-lowering action of spirulina concentrate in rats. J Nutr. Search PubMed
• Chamorro G et al. (1997). Reproductive and peri- and postnatal evaluation of S. maxima in mice at up to 30% of the diet; no reproductive toxicity reported. DOI
• Bahrini I et al. (2025). C-phycocyanin in alloxan-induced diabetic rats at 50–200 mg/kg; reduced pancreatic inflammation and glucose, with no toxicity up to 1 g/kg. J Agric Food Res 21:101951. Record
• Antitumor NK activation in mice. Oral spirulina extract raised NK-cell antitumor activity through the MyD88 pathway. PMC11158122

Spirulina clinical study table: year, design, population and dose

Human studies and pooled analyses, newest first. Findings are those reported by the authors.

Spirulina DOI, PubMed and official source links

Other jurisdictions. The EU register of health claims, the EU novel food catalogue and the Indian FSSAI regulations were not re-verified for this library; consult the official sites directly.

Link policy. DOIs and PubMed IDs appear only where they were seen on a publisher or PubMed record. Entries without them link to a title search.

Known gaps. No human pharmacokinetic studies were found, and several 2021–2025 meta-analyses were not individually checked for first authors. Corrections are welcome.