Research

Mixed

Spirulina supplementation does not significantly reduce waist circumference in the general adult population, though it may benefit obese individuals over 40.

Do not expect Spirulina to significantly reduce waist circumference for the general population. However, if you are obese and over 40, taking ≥2g/day may help. Focus on its proven benefits for overall weight and body fat reduction instead.

ModerateQualifiesMEDIUM confidence
The resulting pooled estimate from the random-effects model indicated that the Spirulina intervention did not significantly change WC (WMD: -0.46 cm; 95% CI: -1.30, 0.37; p = 0.280)... subgroup analysis demonstrated that a high dose (equal to or greater than 2 g/day) of spirulina, intervention on people older than 40 years and obese, leads to reduced WC
Mohammadyasin Lak et al. · Nutrition & Metabolism · 2025

Why this rating

GRADE assessment rated WC as 'Moderate' quality with serious limitations.

Source

Effects of spirulina supplementation on body composition in adults: a GRADE-assessed and dose–response meta-analysis of RCTs

Mohammadyasin Lak et al. · Nutrition & Metabolism · 2025

DOI 10.1186/s12986-025-00959-4

Meta-analysis · 17 studiesCited 5×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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