Overview
Blue-green algae — protein-rich with phycocyanin antioxidant and immune effects.
- Endogenously produced or biosynthesized molecule
- Standardized pharmaceutical- or food-grade supplement
- Combined with cofactors that improve absorption or activity
- Capsule or softgel
- Powder
- Sublingual or buccal
- Liposomal liquid
Forms & variants of Spirulina
Different chemical forms of Spirulina behave differently. Browse each form's mechanism, bioavailability, and best-use context.
Mechanism of action
Phycocyanin inhibits COX-2; rich in protein, B-vitamins, and trace minerals.
- · Phycocyanin inhibits COX-2
- · rich in protein, B-vitamins
- · and trace minerals
Effects on the body
Organ system effects
Evidence-based benefits
Lowers LDL and BP modestly
Moderate evidenceReduces allergic rhinitis symptoms
Limited evidencePotential side effects
- · Heavy metal contamination (untested brands)
Drug interactions
Supplement interactions
- A high-quality multivitaminCovers micronutrient cofactors that support most supplement pathways.
- Omega-3 (EPA/DHA)Foundational anti-inflammatory support that complements most regimens.
No specific avoidances listed.
Dosing & bioavailability
Where to buy
Affiliate links — we may earn a commission at no extra cost to you. Amazon code supplementsch-20 is auto-applied at checkout. We don't endorse specific brands; verify third-party testing (USP, NSF, Informed Sport) before purchase.
Third-party testedIndependently verified Spirulina — look for USP, NSF, or Informed Sport seals on the label for purity and dose accuracy.Spirulina third party tested NSF
CapsulesPre-measured Spirulina capsules — easiest for travel and consistent daily dosing without scoops or scales.Spirulina capsules
PowderBulk unflavored Spirulina powder — best cost-per-gram and flexible dosing for stacking or mixing into drinks.Spirulina powder unflavored
Best sellersMost-purchased Spirulina products on Amazon — a quick way to see what's reviewed widely before you commit.Spirulina best sellerScientific evidence9Show studiesHide studies
Spirulina platensis on immune and metabolic markers
Karkos PD, et al.
Review of spirulina clinical trials.
Improvements in lipids, blood pressure, and allergic rhinitis.
PubMed: Spirulina — Lowers LDL and BP modestly
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Live results for "Spirulina Lowers LDL and BP modestly" across the PubMed/MEDLINE peer-reviewed index.
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PubMed: Spirulina — Reduces allergic rhinitis symptoms
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PubMed: Spirulina — randomized controlled trial
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PubMed: Spirulina — meta-analysis
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PubMed: Spirulina — pharmacokinetics
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PubMed: Spirulina — safety adverse events
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PubMed: Spirulina — dose response
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Google Scholar: Spirulina — clinical evidence
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Cross-database citation index for Spirulina as it relates to "clinical evidence".
Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.