Spirulina
Supplements · Antioxidants · Supplement, Typed Supps
A blue-green algae packed with protein and antioxidant pigments.
Stage by stage
- Intake (Powder or tablet): Digested like a protein- and nutrient-dense food.
- Small intestine (Normal digestion): Protein and micronutrients absorbed through normal digestion.
- Bloodstream (Nutrients absorbed): Protein and micronutrients enter the bloodstream through normal digestion.
- Antioxidant pigments (Complete amino acid profile): Provides antioxidant pigments along with a notably complete amino acid profile for a plant source.
What the evidence supports
- Improving allergic rhinitis (hay-fever) symptoms — limited evidence. A few small randomised trials at around 2 g/day report reduced nasal symptoms, but the studies are small and not yet replicated at scale.
- Improving blood lipids (lowering LDL and triglycerides) — limited evidence. Small trials and meta-analyses suggest modest improvements in cholesterol and triglycerides, though study quality is variable.
- Evidence on Long-term safety, particularly of unregulated products — insufficient evidence. Documented contamination with microcystins (liver toxins) and heavy metals in poorly controlled products means safety depends heavily on sourcing, and long-term data are limited.
Typical dose
1–2 g/day in most symptom studies, with some trials using higher amounts
Upper limit: No established UL
Timing
With food, standard dosing.
Time to effect
- Weeks: Any reported effect in studies.
Medication interactions
- Immunosuppressants: Spirulina can stimulate immune activity, potentially working against these drugs. (moderate)
Common myth
“Spirulina is a complete multivitamin replacement.” In reality: Nutrient-dense, but not a reliable source of B12 despite older claims.
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In the glossary
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