Euglena (Paramylon)
A microalga whose beta-glucan, paramylon, is sold for immunity and gut health. A handful of small manufacturer-run trials report changes in immune markers, but nothing yet shows it meaningfully prevents illness.
Evidence last reviewed: August 2026
What the science says
- Natural killer cell activity Limited evidence
A randomized, double-blind, placebo-controlled trial in apparently healthy adults reported higher natural killer cell activity after Euglena powder. It was a single small trial measuring a laboratory marker rather than actual illness.
- Cold-like symptoms Limited evidence
One randomized controlled trial found fewer self-reported cold-like symptoms when Euglena gracilis was added to the habitual diet. It has not been replicated by an independent group.
- Fatigue Limited evidence
A randomized, double-blind, placebo-controlled trial of a paramylon-containing food in healthy adults reported small improvements in fatigue scores. Single study, subjective endpoint, industry sponsored.
Dosage & safety
Scientific references
- Euglena gracilis (Euglena) powder supplementation enhanced immune function through natural killer cell activity in apparently healthy participants: A randomized, double-blind, placebo-controlled trial
- Incorporating Euglena gracilis into the habitual diet modulates immune function and reduces common cold-like symptoms: a randomized controlled trial
- Effect of Food Containing Paramylon Derived from Euglena gracilis EOD-1 on Fatigue in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Trial
Where to buy
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