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Spirulina

With meals

Spirulina is a blue-green microalgae (cyanobacterium) that has been consumed as a nutrient-dense food source for centuries. It is exceptionally rich in protein, B vitamins, iron, and phycocyanin — the pigment responsible for its deep blue-green color. Spirulina is widely studied for its effects on blood lipids, antioxidant capacity, and allergic responses.

Research Evidence
Alleviates symptoms of allergic rhinitis
Moderate
May reduce exercise-induced fatigue during endurance activity
Limited
Lowers LDL cholesterol in overweight individuals
Moderate
Reduces total cholesterol and triglycerides
Strong
May improve fasting blood glucose levels
Limited
Provides antioxidant and anti-inflammatory effects
Moderate

Expert Evidence

10 references from 3 experts

2025
2021
Safety & Cautions

Side Effects

  • Mild digestive discomfort
  • Nausea at higher doses
  • Potential allergic reaction in sensitive individuals
  • Possible contamination with microcystins if sourced from unregulated producers
Spirulina is generally well-tolerated at standard doses. However, sourcing matters — purchase only from reputable brands that test for heavy metals and microcystin contamination, and individuals with autoimmune conditions should consult a healthcare provider before use due to its immune-modulating properties.
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