Ecdysterone dosage and evidence
Written by Aaron CuhaReviewed Sep 2026
The short answer
In a study in people, those taking ecdysterone gained more muscle and lifted more on the bench press. The researchers thought the effect was strong enough that sport should ban it.
Evidence grade for Ecdysterone: Moderate. The rule: at least one finished study in people, and at least 100 people who took it. The sum on this page: 3 completed trials, 233 people given it. A grade counts how much has been done to people, not whether it works.
- People given it
- 233
- Human studies
- 3
- Found nothing
- 1
Dose
No human dose established
Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose.
3 completed trials, 233 people given it
5 effects reported, 3 unwanted, 2 wanted, by people using it, not a trial
Goal pages: Fat loss and metabolism, Muscle and strength, Heart and circulation
In plain English
In plain English, from Aaron
This is how I would explain it to a friend. The evidence, with the numbers, is further down the page.
Ecdysterone is a steroid found in insects and some plants, like spinach. It is sold as a pill to build muscle. It is shaped like a steroid but does not act like testosterone. It is a supplement, not an approved drug.
What people take it for
- More muscle without taking real steroids.
- More strength in the gym.
- Less body fat.
What studies in people showed
The biggest test was the drug version, given to 233 older adults losing muscle with age. When everyone was counted, it missed its main target on walking speed. In a smaller study in people, those taking ecdysterone gained more muscle and added more to their bench press. Liver and kidney blood tests did not rise. The team checked the pills for hidden steroids first. They said the effect was strong enough that sport should ban it. A third study in 20 young men who lift found some fat loss, but only arm fat clearly beat the dummy pill. That study is far too small to settle anything.
What people report
Reports, not study results
The good
- Some people report big effects. Others report nothing at all.
- A few describe effects the ads do not mention, like handling stress and workload better, or changes in sex drive.
The bad
- Many people ran it and saw no change in size or strength.
- People on steroid forums mostly dismiss it. That is their opinion, not a test.
- People do not trust the labels. Forum users paid a lab to test a related product because they doubted what was in it.
Where these come from: Forum patterns from T-Nation, MESO-Rx and ExcelMale, read in September 2026. These are not from a study. The study results are from the papers on this page.
My bottom line
This one has a real result in people, which is more than most gym supplements. But the biggest test missed, and your bottle is not the product in the study. Train hard and eat your protein first. If you compete, the ban question alone is a reason to skip it.
An opinion, not a finding. I am a coach, not a doctor.
What it has been measured to do
Measured in people
Goals Ecdysterone has been tested for in people, biggest studies first. We count only what the studies on this page say, so the real numbers may be higher.
- Keeping or building muscle233 people · 2 studies · 1 found nothing
- Getting stronger233 people · 2 studies · 1 found nothing
- Kidney functionno headcount stated · 1 study
- Losing fat specificallyno headcount stated · 1 study
What people using it report
Real people telling you what happened to them. Nobody checked it, and the people who post are not a fair sample, so it cannot prove anything works. It is still the best guide on this page to what people actually do with Ecdysterone, what they expect, and what goes wrong. The full account, including the negative reports, is below.
31 of the 36 indexed goals have no study of any kind behind Ecdysterone
No study in people, animals or cells on this page reports a result for these. That does not prove Ecdysterone does nothing for them. It does mean anything you have heard about Ecdysterone and one of these did not come from a study cited here.
Show full evidence
What is Ecdysterone?
In a study in people, those taking ecdysterone gained more muscle and lifted more on the bench press. The researchers thought the effect was strong enough that sport should ban it.
Ecdysterone is the one in this family worth taking seriously. Its best known study in people stands out in two ways.
First, it worked. People taking ecdysterone gained more muscle than the comparison group. They also added more to their best single bench press. Blood tests for liver and kidney damage did not go up. The same growth showed up in muscle cells in a dish.
Second, the researchers did not use that to sell it. They said the result was strong enough that it should go on the World Anti-Doping Agency's banned list. A team saying their own compound should be banned in sport is a stronger signal than a team saying it should be sold.
They also checked everyone for banned drugs first, and tested the supplement for hidden steroids. That answers the usual doubt about good results in this area.
The drug version of the same molecule had a bigger test in 233 older adults losing muscle with age. On walking speed, it missed its main target.
How does Ecdysterone work?
Ecdysterone is shaped like a steroid, but it does not attach to the testosterone receptor. That is why people say it builds muscle without steroid side effects. The best supported idea is that it works through a different receptor, one of the estrogen receptors. That switches on the signals that tell muscle to build protein. The drug company that tested it describes a second route through a different receptor, called MAS, which is part of a system that guards against muscle loss. Two believable explanations for one molecule is a sign nobody has settled how it works.
What have studies in people found about Ecdysterone?
Good for a supplement in this group. One study found more muscle and strength. A second small study looked at fat and blood sugar. And a drug version was tested in 233 older adults.
- The biggest test: the drug version was given to 233 older adults losing muscle with age. Across everyone who took part, it missed its main target on walking speed.
- In a study in people, those taking ecdysterone gained more muscle and added more to their best single bench press.
- Blood tests for liver and kidney damage did not go up in that study.
- That study checked people for banned drugs first and tested the supplement for hidden steroids. That removes the usual doubt about good results here.
- A separate small study in 20 men who lift weights looked at fat burning and blood sugar control.
- The researchers behind the strength study said it should be added to the banned list in sport.
What this does not tell you: The strength study was a real test with a comparison group, but it was not large. Most of the swallowed dose does not reach the blood, so nobody knows the right dose, and how a product is made matters a lot. Two different ways it might work have been proposed, which suggests nobody knows for sure. And the biggest, best test of the molecule, the drug version in 233 older adults, did not hit its main target when everyone was counted.
What do people who took Ecdysterone report?
This is what real people say happened to them, good and bad. Nobody measured it. A report cannot tell a real effect from the lift people get just from expecting it to work, from a diet or training change made at the same time, or from what was really in the vial. We still put it near the top. It is the next best thing to a study in people: what happens when real people use it, including what goes wrong.
- Reports range from substantial effects to nothing at all, and the spread is wide enough that posters treat it as the defining feature of the compound rather than as ordinary variation.
- Muscle gain is the claim it is tested against and the claim that most often fails. Accounts of running it and seeing no change in size or strength are common, including from people who report other effects from the same bottle.
- The effects people do describe sit to one side of the marketing: better tolerance of stress and workload in one account, changes in libido and ejaculate volume in another.
- On the steroid-using boards the prevailing position is dismissal, on the grounds that people with access to real steroids have no reason to bother with a plant extract. That is a stance held by that community rather than a test of anything.
- Product content is a live problem and the discussion runs together with turkesterone rather than staying separate. At least one commercial turkesterone product was put through HPLC testing by the community specifically because the label was not trusted, which is the clearest signal in the whole discussion about how these products are regarded.
Sources: Ecdysteroid threads on T-Nation and MESO-Rx, with ExcelMale mentions, found by site-restricted search, September 2026. Nothing above is attributed to any specific post and no post is reproduced.
The state of the research
Ecdysteroids are steroid hormones that control shedding of the shell in insects. Some plants have them too, like spinach, quinoa and Ajuga turkestanica. They are not built like testosterone and do not attach to its receptor. That is where the claim comes from that they build muscle without steroid side effects. Read this family together, not one at a time. Ecdysterone, also called 20-hydroxyecdysone, has a study in people that found more muscle and bench press strength. Its drug version was tested in 233 older adults losing muscle with age, and missed its main target when everyone was counted. Turkesterone, the one the ads push hardest, has never been tested in people at all. Results for one member do not carry over to another. The one with the most proof is not the one sold hardest.
The honest summary for ecdysterone is this. It has better proof in people than most things in a supplement shop, and weaker proof than its biggest fans claim. The study that found more muscle and bench press strength is real. The same molecule missed its main target when a drug company ran a careful test in 233 older adults, measuring walking speed. Both results belong to the same compound.
The evidence, in charts
Fig. 1a · how many people
233people, across 1 study in people cited here
| Study | People | Share |
|---|---|---|
| Journal of Cachexia, Sarcopenia and Muscle 2025 | 233 | 100% |
The whole total is one study of 233. Counts are the number of people each study on this page says it signed up. That includes studies that only watched people and gave nobody the compound. 2 more studies in people give no headcount and are not counted here. Studies still signing people up are left out, and only studies cited on this page are counted.
Fig. 1b · evidence mix
All 3 sources here are studies in people.
- Study in people · done in people3100%
Counted from the list of sources on this page. It counts only what we cite, so there may be more studies out there. A review counts once, however many studies it sums up.
Fig. 2 · evidence over time
Sources here come from just two years, 2019 and 2025.
Too few different years on this page to draw a timeline.
Fig. 3 · legal status at a glance
US
Not approved
UK
Not approved
AU
Not approved
CA
Not approved
Not approved in any of the four countries shown. This is what the law says, not a verdict on the science. See Legal status below for the full text and any notes.
Fig. 4 · how much does what
Nobody has tested different amounts in people
This chart would show how the effect changes as the amount goes up. For this compound, nobody has measured that in people. So we leave it empty. We will not borrow an animal chart and pretend it works the same in people.
Fig. 5 · what the molecule is
- Kind of compound
- Supplement
- Molecule weight
- 480.6 Da. A polyhydroxylated steroid, not a peptide.
- Half-life
- Stated in words, not a numbersee the exact wording below
- Chain length
- None on file
Half-life as stated on file: Short, with oral bioavailability generally reported as poor, which is the main obstacle to translating cell and animal results. No single agreed human figure was resolved in the sources loaded.
No amino acid sequence is on file for Ecdysterone, which is expected: a supplement is not built from amino acids.
The studies we cite
- Study in people2019Ecdysteroids as non-conventional anabolic agent: performance enhancement by ecdysterone supplementation in humans
In a study in people, those taking ecdysterone gained more muscle than the comparison group and lifted more on the bench press. Blood tests for liver and kidney damage did not rise. The researchers checked everyone for banned drugs and tested the supplement for hidden steroids first. They said it should go on the banned list in sport. That is how strong they judged the effect. In a dish, the same growth showed up in muscle cells.
A controlled clinical trial in humans. Significantly higher increases in muscle mass in participants dosed with ecdysterone, and significantly more pronounced increases in one-repetition bench press performance. The same hypertrophic effect appeared in C2C12 myotubes in vitro. No increase in liver or kidney toxicity biomarkers. Participants were screened for prohibited performance-enhancing substances and the supplement was tested for anabolic steroid contamination before administration. The authors conclude their results strongly suggest including ecdysterone on the prohibited list in class S1.2, other anabolic agents.
- Study in people2025Effects of asparagus-derived 20-hydroxyecdysone supplementation on fat oxidation and insulin sensitivity in resistance-trained males
20 young men lifting weights took the plant extract or a dummy pill for twelve weeks. The extract group lost fat from the arms, legs and belly, and burned more fat. Their fasting insulin fell. But only the arm fat result was clearly better than the dummy pill group. Ten men per group is far too small to settle anything.
20 healthy males, 10 per arm, 30 mg a day of 20-hydroxyecdysone or placebo across 12 weeks of supervised resistance training. Arm, leg and abdominal fat all fell, though only arm fat separated from placebo between groups. Fat oxidation rose at rest and during exercise, with a between group difference only at 40 percent of VO2peak. Fasting insulin and free fatty acids fell and QUICKI rose. Ten per arm is the limitation. A second randomised human study of the same molecule from an independent group and a different source material.
- Study in people2025BIO101 in sarcopenic seniors at risk of mobility disability: results of a double-blind randomised interventional phase 2b trial
The drug version of this molecule was tested in 233 older adults losing muscle with age. It missed its main target. Across everyone who took part, walking speed over a 400 metre course barely changed compared with a dummy pill. A smaller group who stuck to the plan walked a little faster. Counting only those people is not the fair test. Full detail is on the BIO101 page.
The pharmaceutical-grade version of this molecule in 233 older adults with sarcopenia. The primary endpoint, gait speed on a 400-metre walk, improved 0.07 m/s against placebo in the full analysis set and was not significant, and improved 0.09 m/s in the per-protocol population at p = 0.008. Detail on the BIO101 page.
Common questions
Has Ecdysterone been tested in people?
Yes. 233 people given it across 3 completed trials cited here, 1 of which found nothing. In a study in people, those taking ecdysterone gained more muscle and lifted more on the bench press. The researchers thought the effect was strong enough that sport should ban it.
What is the Ecdysterone dosage?
No human dose established. Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose. 3 completed trials, 233 people given it
Is Ecdysterone FDA-approved?
Sold as a dietary supplement in the United States. Not an approved drug. Its drug version, BIO101, is investigational, meaning still being tested.
Does ecdysterone actually build muscle?
In one study in people, yes. Those taking it gained more muscle and added more to their bench press. Liver and kidney blood tests did not rise, and the supplement was checked for hidden steroids first. That is a real result. But the biggest test of the same molecule, in 233 older adults losing muscle with age, missed its main target when everyone was counted.
Why did the researchers want it banned?
Because they found it worked. They wrote that their results strongly suggest ecdysterone should go on the banned list, under other muscle-building drugs. A team asking for their own compound to be banned in sport is a more believable sign of an effect than an ad.
Is it a steroid?
It is shaped like a steroid, but it is not like testosterone. It does not attach to the testosterone receptor. That is why it is not expected to cause the hormone side effects of anabolic steroids. It also means ads that compare it to testosterone are wrong in both directions.
How does it compare to turkesterone?
Ecdysterone has studies in people. Turkesterone has none. That is the whole comparison, and it runs the opposite way to how the two are sold.