Beta-Ecdysterone
Commonly used for
Muscle & StrengthAthletic Performance
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The cheapest product is usually low quality, but more expensive doesn’t always mean better.
What is it? / Overview
Ecdysterone appears to induce skeletal-muscle hypertrophy via estrogen-receptor-beta activation and IGF-1 signaling -- a non-androgenic pathway distinct from anabolic steroids. A 10-week randomized trial found greater muscle mass and bench-press gains versus placebo, and the study authors themselves recommended it for WADA prohibition given the anabolic-like effect size. This is a single positive trial that needs independent replication, and severe underdosing/counterfeiting is common in commercial products.
How is it used? / Administration
Form: 20-hydroxyecdysone ('ecdysterone'), a phytoecdysteroid from spinach, quinoa, or (commonly, and often counterfeited) Cyanotis arachnoidea
Typical dose studied: The one positive human trial used up to ~800 mg/day -- but real-world commercial product content is frequently far below what's on the label
Timing: Daily during a resistance-training block
The WADA-monitoring status is the sharpest practical flag -- any competitive, drug-tested athlete should be steered away regardless of the muscle-building evidence.
How well does it work? / Evidence
? Emerging / limited evidence
Who should avoid it?
Already taking it? Worth knowing two things: it's on WADA's monitoring list, so competitive tested athletes should avoid it, and independent testing has found some commercial products contain a small fraction of their labeled ecdysterone content (sometimes counterfeited with cheaper Cyanotis extract) -- product quality is a real, documented problem in this category.
Research & references
Isenmann E et al. (2019). Ecdysteroids as Non-Conventional Anabolic Agent: Performance Enhancement by Ecdysterone Supplementation in Humans. Archives of Toxicology. Dissemond J et al. (2025). How Reliable Is the Labeling of a Commercial Phytosteroid Product? A 12-Week Randomized Double-Blind Training Study. Journal of the International Society of Sports Nutrition. Hunyadi A et al. (2016). Ecdysteroid-Containing Food Supplements From Cyanotis Arachnoidea on the European Market: Evidence for Spinach Product Counterfeiting. Scientific Reports.
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