Heart/Inflammation/Weight

Spirulina

Blue-green algae rich in phycocyanin that may modestly lower cholesterol and blood pressure in adults with elevated lipids.

score

evidence

Caution

risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Overview

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Safety

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Quick Take

Worth considering if your LDL or blood pressure is elevated; effects are modest and product quality matters heavily.

Spirulina is a biomass of cyanobacteria (Arthrospira platensis) traditionally consumed for its dense protein, vitamin, and mineral content. Its active pigment, phycocyanin, acts as a potent antioxidant and inhibits NADPH oxidase, which may reduce oxidative stress and downstream inflammation. Clinical trials and meta-analyses show modest but consistent improvements in lipid profiles and blood pressure, particularly in people with mild metabolic dysfunction. It may also dampen nasal inflammation in allergic rhinitis and slightly improve fasting glucose.

Potential benefits

Lowers LDL and triglycerides

Lowers blood pressure

Reduces allergic rhinitis symptoms

Lowers inflammatory markers

Improves fasting glucose

May improve endothelial function

Protocol

Amount

3-10 g

Frequency

Once daily, or split into two doses

When

With meals to reduce gastrointestinal discomfort and improve tolerability.

Onset Time

8-12 weeks for lipid and blood pressure changes; 1-3 weeks for allergic.

Who Should Consider

Adults with elevated LDL or triglycerides

People with mild hypertension

Those with allergic rhinitis

Health-conscious adults seeking plant protein

Food Sources

No common dietary equivalent — consumed as a dried algae supplement

How It Works

Phycocyanin in spirulina inhibits NADPH oxidase and scavenges free radicals, reducing lipid peroxidation and pro-inflammatory cytokine release. Its peptides may also inhibit cholesterol absorption and improve vascular nitric oxide bioavailability, contributing to small reductions in LDL and blood pressure.

Updated 5/19/2026