Yerba mate extract,
does it really help with Reduced body weight, body fat, and waist circumference?
research showsYerba mate is rated C. A 30-participant Korean double-blind 12-week trial found positive fat-mass and body-fat-percentage outcomes, but weight, BMI, and waist circumference were null, and an ingredient supplier supported the study. In the latest meta-analysis, the weight-related axis comprised eight trials and 654 participants; BMI was lower by 0.17 and waist circumference by 0.48 cm, neither significantly. Weight, BMI, and waist reduction are rated D, the limited body-fat signal C, and attribution of caffeine or combination-product effects to mate alone remains ?, giving an overall C with 42 points.
ads claimMarketing converts stimulant effects, temporary appetite changes, and combination-product results into proven fat burning by mate alone.
Useful facts when choosing a product
- Yerba mate is a tea or extract from Ilex paraguariensis leaves that contains caffeine and theobromine.
- Infusions, capsules, and concentrated extracts vary in caffeine and polyphenols, so the 3.15-g daily trial cannot represent every product.
- Weight-loss blends with guarana, green tea, or added caffeine cannot identify which ingredient caused an outcome.
- Insomnia, palpitations, anxiety, and gastrointestinal discomfort can occur, and clinically apparent liver injury appears possible but exceedingly rare.
Chamgap Semantic Classification Code
Candidate index · review held
S.yerba-mate-extract.UNK.body-weight-body-fat-and-waist-circumference.reduce.placeboSupplements and nutraceuticals > Yerba mate extract > Unknown > body weight, body fat, and waist circumference > Reduction claim > Placebo
An automated migration candidate, not an issued permanent code; exact claim scope remains under review. This machine-generated migration candidate helps retrieval but is not a permanent assignment. The original verdict ID and URL remain authoritative.
What the research actually shows
In the 30-person trial, fat mass had P=0.036 and body-fat percentage P=0.030, whereas weight had P=0.387 and waist circumference P=0.113. In the 2025 meta-analysis, the weight-related axis included eight trials and 654 participants; BMI was lower by 0.17 and waist circumference by 0.48 cm, neither significantly. Results from caffeine, guarana, or green-tea combinations were not assigned to mate alone.
Why this is classified as C (42)
A small single-product trial provides fat-mass and body-fat-percentage signals, but weight, BMI, and waist results were null. Supplier support and null pooled BMI and waist findings across the latest weight-related axis of eight trials and 654 participants give C with 42 points.
Counterpoint. Caffeine-sensitive people, pregnancy, lactation, and arrhythmia require attention to total caffeine, and jaundice warrants discontinuation.
Rejudgment record. New verdict — Balanced partial benefit in a small supplier-supported product trial against null BMI and waist findings in a recent randomized-trial meta-analysis and attribution problems
Sub-claim grades by effect
This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.
| Effect (sub-claim) | Grade | Basis |
|---|---|---|
| Reduction in weight, BMI, and waist circumference | D | The Korean trial and latest meta-analysis found null weight, BMI, and waist outcomes. |
| Reduction in fat mass and body-fat percentage | C | Evidence is limited to a small product-specific positive signal. |
| Attribution of caffeine and combination-product effects | ? | The effect cannot be attributed to mate alone. |
Cross-check — AI research and Codex final gate
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Kim SY et al. 2015 | Randomized double-blind placebo-controlled trial | 30 Korean adults with obesity for 12 weeks | Government grant plus support from ingredient supplier Bluegreenlink | Weight, body fat, waist circumference, and waist-to-hip ratio | Fat mass, body-fat percentage, and waist-to-hip ratio were positive; weight and waist were null. | Small product-specific positive signal |
| Li D et al. 2025 | Systematic review and meta-analysis of randomized trials | 13 randomized trials overall; eight trials and 654 participants in the weight-related axis | Academic research | Metabolic, weight, BMI, and waist outcomes | In the weight-related axis, BMI was lower by 0.17 and waist circumference by 0.48 cm, neither significantly. | Recent conflicting synthesis |
Receipt — 3 References
All 3 cited sources were verified for existence at the original page (as of 2026-07-19).
Final verification and publication gate: Codex · Evidence date: 2026-07-19 · Corrections: none
Cite this verdict
[Chamgap] Yerba mate extract x reduced body weight, body fat, and waist circumference — Evidence Grade C·42. 3 cited sources checked. Source: https://chamgap.com/en/verdicts/weight/yerba-mate-extract-weight-body-fat-waist/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.