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Science & Research

Turkesterone Finally Tested on IGF-1 in Men. The Results Were Not What Influencers Promised

Coach Ryan · · 3 min read

The Study in One Line

A small Baylor University-led team gave eleven young men turkesterone and found no statistically significant effect on IGF-1, resting metabolic rate, or fat and carbohydrate metabolism. The numbers drifted in the direction supplement marketers would like, but they did not clear the bar for statistical significance.

Turkesterone is a plant-derived ecdysteroid that social media promotes as a "natural steroid" with muscle-building power and none of the downsides of anabolic androgenic steroids (AAS). It has been consumed widely with little human data behind it. This paper, published in Muscles in 2024, is one of the first attempts to test the hype in people.

What the Researchers Actually Did

The study was a placebo-controlled preliminary investigation. Eleven apparently healthy males (average age 23.3 ± 2.2 years) volunteered. Participants received turkesterone at multiple acute doses, compared against placebo. Researchers collected samples at three points:

  • Pre-ingestion (baseline)
  • 3 hours post-ingestion
  • 24 hours post-ingestion

The main outcomes were serum IGF-1, a hormone tied to muscle protein synthesis and growth signaling, and resting metabolic rate (RMR), which was measured to test the claim that turkesterone boosts thermogenesis. Lipid and carbohydrate metabolism markers were also tracked. The abstract does not specify the exact milligram doses, so this article does not either.

The Headline Result: Nothing Significant

The statistical analysis found no significant main effect of condition, time, or interaction for serum IGF-1, RMR, lipid metabolism, or carbohydrate metabolism (all p > 0.05). In plain terms, the researchers could not distinguish turkesterone's effects from placebo or from normal fluctuation over time.

That is the finding. Everything else is secondary.

The "Trend" Everyone Will Want to Quote

The authors did note two non-significant patterns:

  1. IGF-1 rose under both turkesterone conditions and stayed elevated relative to placebo.
  2. RMR stayed above baseline across the 3 hours measured.

A non-significant trend is not a hidden positive result. With only 11 participants, the study had limited power to detect real but modest effects, so these patterns could reflect a true signal that a larger study would confirm. They could also be random noise. This design cannot tell the difference, and the authors say as much, describing their data as failing to "fully support turkesterone as a potent anabolic supplement."

Why This Study Can't Settle the Question

Several limitations matter if you plan to act on this research:

  • Tiny sample. Eleven young, healthy men is a pilot-scale group, and the results may not apply to women, older adults, or trained lifters.
  • Acute dosing only. The study looked at hours and a single day, not weeks of supplementation alongside training.
  • Indirect measures. IGF-1 is a proxy. No muscle size, strength, or muscle protein synthesis was measured, so no conclusion about hypertrophy is possible.
  • No training component. Real-world muscle growth depends on resistance exercise, protein intake, and time. None of that was tested here.

The authors explicitly call for future work to assess turkesterone-mediated IGF-1 changes on long-term whole-muscle growth across several training sessions.

The Good News: Tolerability

The researchers highlighted a favorable hemodynamic and gastrointestinal tolerability profile. At the doses tested, over this short window, turkesterone did not cause notable cardiovascular or stomach problems in these participants. That is useful, but it is a short-term safety signal in 11 people, not proof of long-term safety.

What This Means for You

Does it build muscle? There is no proof yet. This study did not measure muscle growth, and the hormone and metabolic outcomes were not significantly different from placebo.

Dose: No evidence-based dose for muscle building exists. The abstract doesn't report the doses used, and nothing here validates any product label or influencer protocol.

Timing: Measurements were taken at 3 and 24 hours after ingestion, so the data offer no basis for a timing strategy such as pre-workout or with meals.

Who it might be for: Curious, healthy adults who accept that the benefit is unproven and want to wait for better data. Spending money on it should not come at the expense of the basics: progressive resistance training, adequate protein, sleep, and total calories.

  • Anyone expecting steroid-like results. Nothing in this study supports that comparison.
  • People with hormone-sensitive conditions, or those taking medications, who haven't talked to a clinician.
  • Pregnant or breastfeeding individuals, and anyone under 18.
  • Competitive athletes subject to drug testing, who should check their governing body's rules and the contents of any product first.

The Bottom Line

The first human data on turkesterone and IGF-1 don't show a significant effect. They show a trend that might be real, in a sample too small and a window too short to know. Until longer trials measure actual muscle growth, treat turkesterone as an unproven supplement, not a natural shortcut to steroid-level gains.

Original study

Read the original research on pubmed.ncbi.nlm.nih.gov →

This article summarizes published research for general information. It is not medical advice.

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Coach Ryan

Coach Ryan writes for Dr. Gymbro: science-backed fitness, nutrition & performance.

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