Myth-buster
Spirulina for weight in kids? A meta-analysis found no significant effect — and the trend actually pointed toward less weight, not more.
This systematic review contradicts the mostly positive direction of earlier smaller studies, making the overall picture contested — the pooled result is null, but confidence is moderate, so this doesn't settle the question.
Researchers combined data from 5 studies on spirulina and weight in children and adolescents. The pooled effect was not statistically significant (SMD = -0.526, p = 0.176), meaning spirulina didn't reliably change body weight in this population. The result pushes against the prevailing belief that spirulina helps with weight control, but the small number of studies limits how definitive we can be.
Where this fits in the evidence
Pillser has synthesized 5 studies on Spirulina for Reduced Body Weight — overall evidence strength: Moderate.
Across 5 studies, 4 reported small beneficial effects of spirulina supplementation on reduced body weight, with statistically significant reductions observed in 4 studies. The most robust evidence comes from a systematic review and meta-analysis in overweight and obese adults (small effect, g = -0.30, 95% CI: -0.53 to -0.08), while one neutral finding was noted in a pediatric meta-analysis. Effect sizes were predominantly small, and doses ranged from 20 mg to 6 g per day, though many studies did not consistently report dose or form.
The study
- Systematic Review
- 2026-03-16
- Frontiers in nutrition
This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.