Research synthesisModerate evidenceSmall effect5 studies · 4 beneficial · 1 neutral · 0 harmful
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.
- Studied populations: overweight and obese adults, adults with metabolic syndrome
Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). The one neutral study focused on children and adolescents, suggesting effects may not generalize to younger populations. Study durations and forms were not consistently reported, limiting precision in dosing recommendations.
Generated Jul 9, 2026