CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-07-20). The draft was written by AI, the existence of all 3 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.6.
Verdict No. 838 · Search date 2026-07-20 · Methodology v0.6

Turkesterone,
does it really help with Increased muscle mass and strength through a natural anabolic action?

30-Second Summary
D
Evidence Grade D · 24 · Safety unknown
Direct human evidence found no body-composition benefit, and strength was not measured
What the
research shows
Turkesterone receives D with 24 points. A 2024 randomized placebo-controlled trial in 31 adults assessed only DXA body composition after four weeks of 500 mg/day and found no benefit for lean mass, body mass, or fat mass. It did not measure handgrip or any other strength outcome and must not be described as a null strength trial. A separate 11-person acute crossover study found no significant effect on IGF-1 or resting metabolic rate and did not longitudinally assess hypertrophy or strength. One small null body-composition trial and no positive human trial support D but do not amount to repeated refutation for F.
What the
ads claim
Marketing converts cell and animal protein-synthesis findings or human evidence for a different compound, ecdysterone, into natural-steroid muscle gains from turkesterone. Turkesterone and ecdysterone are not the same molecule, and current direct turkesterone human evidence does not support that extrapolation.
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Useful facts when choosing a product

  • Turkesterone is an ecdysteroid compound found in plants and arthropods; it is not testosterone or an approved anabolic medicine.
  • Human findings for ecdysterone do not automatically apply to products containing the different molecule turkesterone.
  • Analyses of commercial sports supplements have found discrepancies in labeled amounts of botanical performance ingredients and undeclared compounds, making third-party test certificates important.
  • Long-term human safety, drug interactions, and reproductive, hepatic, and cardiovascular effects remain poorly characterized, and athletes must separately check current anti-doping rules and contamination risk.
Gap Measurement · Verdict 838 · D 24
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

Antonio and colleagues studied 31 active adults, including 14 men and 17 women, who received turkesterone 500 mg/day or placebo for four weeks and underwent DXA body-composition assessment only. Lean-mass change was -0.6±1.4 kg with turkesterone and -0.3±1.7 kg with placebo, with between-group p=0.68; handgrip and other strength outcomes were not measured. Harris and colleagues used a crossover design in 11 men receiving 1,000 mg, 2,000 mg, or placebo and found no significant condition effect on IGF-1 or metabolic measures, without longitudinal muscle-mass or strength assessment. Cohen and colleagues found major label-accuracy and undeclared-ingredient problems in 57 sports supplements.

02

Why this is classified as D (24)

A 31-person four-week randomized trial was null for DXA lean mass, body mass, and fat mass but did not measure strength. An 11-person acute trial was null on indirect markers, and no positive human trial exists, supporting D with 24 points for limited direct null evidence. The absence of a large independent trial and a direct strength test prevents F; label and purity concerns remain separate under safety.

Counterpoint. Progressive resistance training, adequate protein and energy, and sleep have far stronger support, and repeatedly validated options such as creatine take priority over turkesterone.

Rejudgment record. New verdict — Applied D because a 2024 randomized placebo-controlled four-week trial in 31 adults was null for DXA body composition and did not measure handgrip or other strength outcomes, while an 11-person acute crossover trial was null for IGF-1 and resting metabolic rate and no positive turkesterone-specific human trial exists

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)GradeBasis
Improved human muscle mass and body compositionDA direct four-week randomized trial in 31 adults found no improvement in DXA lean mass, body mass, or fat mass and did not measure strength.
Natural anabolic surrogate effects in humansDAn 11-person acute crossover trial found no significant condition effect on IGF-1 or resting metabolic rate.
Long-term high-dose safety and efficacy of standardized products?Long-term human data are absent and actual-content variability prevents product-wide generalization.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Antonio J et al. 2024Four-week randomized double-blind placebo-controlled trial17In-kind product donation from Nutrition Formulators; supplement-industry links disclosedDXA body mass, lean mass, and fat massA dose of 500 mg/day did not improve lean mass (p=0.68), body mass, or fat mass over placebo. Handgrip and other strength outcomes were not measured.Key direct null human trial
Harris DR et al. 2024Randomized single-blind placebo-controlled acute crossover trial11Baylor departmental grant and Texas ACSM student research supportIGF-1, resting metabolic rate, substrate use, blood pressure, and acute tolerabilitySingle 1,000- and 2,000-mg doses did not significantly alter IGF-1 or metabolic measures versus placebo and did not longitudinally assess muscle mass or strength.Null surrogate evidence, not a direct hypertrophy trial
Cohen PA et al. 2023Quantitative analysis of commercial sports-supplement ingredients57Independent support including Consumers Union and Pew Charitable TrustsDetection and amount of labeled ingredients and undeclared compoundsProducts marketed with turkesterone and related botanical performance ingredients showed actual-content discrepancies and undeclared compounds.Product-quality and safety evidence
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Receipt — 3 References

All 3 cited sources were verified for existence at the original page (as of 2026-07-20).

Antonio J, Silver T, Lukowiak A, Jiannine LM. A Preliminary Investigation of Turkesterone: It's Not Deca. Research Directs in Health Sciences. 2024;4(1). DOI: 10.53520/rdhs2024.104126.
checked
Harris DR, Chapman-Lopez T, Machek SB, Forsse JS, Sulak T, Funderburk LK. The Effects of Multiple Acute Turkesterone Doses on Indirect Measures of Hypertrophy and Metabolic Measures: A Preliminary Investigation. Muscles. 2024;3(4):364-375. PMID: 40757520. PMCID: PMC12121319. DOI: 10.3390/muscles3040031.
checked
Cohen PA, Avula B, Katragunta K, Travis JC, Khan I. Presence and Quantity of Botanical Ingredients With Purported Performance-Enhancing Properties in Sports Supplements. JAMA Netw Open. 2023;6(7):e2323879. PMID: 37459101. PMCID: PMC10352857. DOI: 10.1001/jamanetworkopen.2023.23879.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-20 · Corrections: none

Cite this verdict

Turkesterone x natural anabolic increases in muscle mass and strength Evidence Grade D card
[Chamgap] Turkesterone x natural anabolic increases in muscle mass and strength — Evidence Grade D·24. 3 cited sources checked. Source: https://chamgap.com/en/verdicts/sports/turkesterone-muscle-mass-strength-natural-anabolic/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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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.