Spirulina

ProteinAntioxidantImmune

Dense, nutrient-rich blue-green algae — high-protein, packed with B vitamins, iron, and phycocyanin. Best evidence is in lipid lowering and allergic rhinitis.

EvidenceModerate

Moderate evidence for lipid improvement (LDL, triglycerides), blood pressure reduction, and allergic rhinitis symptom relief. Modest for exercise performance, fatigue. Effects: 8–12 weeks.

Spirulina is a spiral-shaped cyanobacterium (technically not algae, but commonly classed with them). It's about 60% protein by weight with a complete amino acid profile, plus generous B vitamins, iron, and beta-carotene. Its signature blue pigment phycocyanin is a potent antioxidant. Used as food by Aztecs and Africans around Lake Chad for centuries; NASA studies confirmed it could be a viable astronaut food. Modern human RCTs show modest lipid improvements, blood pressure reduction, allergic rhinitis relief, and immune support.

Form
Spirulina powder or tablets from clean-water sources (Hawaiian Pacifica, Earthrise — third-party tested for heavy metals and microcystins). Avoid cheap, unverified brands.
Dose
3–10 g/day for general use. Higher doses (5–8 g) in lipid / allergic rhinitis trials.
Timing
With or without food. Anytime.
Schedule
Daily.
Side effects
Generally well-tolerated. GI upset, headache, mild allergic reactions. Quality issues: contaminated spirulina can contain microcystins (liver toxin) or heavy metals.
Interactions
Immunosuppressants — opposing (mildly immune-stimulating). Anticoagulants — mild additive.
Contraindications
PKU (phenylketonuria — contains phenylalanine). Autoimmune disease (relative — immune-stimulating). Allergy to iodine / shellfish (some spirulina-related cross-reactivity rare). Pregnancy / breastfeeding (only certified-clean products).
Lab markers
Lipid panel. BP. Ferritin if relying on it for iron.
Food sources
Spirulina IS food — eaten as a powder, in smoothies, or as flakes in some cuisines.

Pairs with

Chlorella (complementary algae — different nutrient profile, often combined). Vitamin C, B-complex (synergistic).

within Algae, sea & superfoods