Supplement analysis backed by scientific evidence · PT

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Limited evidenceLongevity & antioxidants

Phycocyanin

The blue pigment-protein from spirulina, sold as a concentrated antioxidant. Human data are thin: one safety trial of a phycocyanin-enriched extract and a handful of trials of whole spirulina, which is not the same product.

Evidence last reviewed: August 2026

What the science says

  • Safety at high doses Moderate evidence

    A randomized double-blind placebo-controlled study gave a high dose of phycocyanin-enriched spirulina extract and found no meaningful effect on coagulation or platelet activation, addressing a specific safety concern. This was a safety endpoint study, not an efficacy trial.

  • Anti-inflammatory and antioxidant effects Limited evidence

    A triple-blinded randomized placebo-controlled trial of whole spirulina in people with relapsing-remitting multiple sclerosis reported reductions in some inflammatory markers and improved quality-of-life scores. The intervention was whole spirulina, so the contribution of phycocyanin specifically is unknown.

Dosage & safety

Studied doseNo efficacy-based dose. The safety trial used a phycocyanin-enriched extract at doses corresponding to several grams of spirulina; commercial blue spirulina powders typically supply 500–2,000 mg/day.
SafetySpirulina products are generally well tolerated, but they can be contaminated with microcystins, heavy metals or other cyanobacteria — buy tested products. Avoid if you have phenylketonuria (phenylalanine content) or an autoimmune condition on immunomodulating treatment, and avoid in pregnancy without medical advice.

Scientific references

Where to buy

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