Laxogenin, usually sold as 5-alpha-hydroxy-laxogenin, is a synthetic steroid compound marketed as a natural muscle-building supplement. Despite bold claims on supplement labels, there are no published human clinical trials showing it increases muscle mass, strength, or protein synthesis. What limited lab research exists paints a complicated picture, and the FDA has taken the position that it isn’t a lawful dietary supplement ingredient at all.
What Laxogenin Actually Is
Supplement companies often describe laxogenin as a “plant steroid” or “brassinosteroid” extracted from plants like Smilax. In reality, 5-alpha-hydroxy-laxogenin is a synthetic spirostane-type steroid. It’s manufactured in a lab, not extracted from herbs. Its chemical structure resembles certain plant steroids, but the version in supplements is a synthetic analog designed to be biologically active in humans.
This distinction matters because it undercuts the “natural” framing you’ll see on most product labels. The FDA has explicitly stated that 5-alpha-hydroxy-laxogenin does not qualify as a dietary ingredient under federal law. It’s not a vitamin, mineral, amino acid, herb, or botanical. In a 2022 warning letter to a supplement company, the agency classified products containing it as adulterated, meaning they cannot be legally marketed in the United States.
The Claims vs. the Evidence
Laxogenin is advertised as boosting protein synthesis by up to 200%, building lean muscle, and aiding fat loss, all without affecting hormone levels. You’ll find these claims repeated across supplement websites, forums, and product labels. None of them are supported by published human studies.
The most commonly cited figure, a 200% increase in protein synthesis, appears to originate from unpublished or proprietary data that has never been verified in a peer-reviewed journal. No controlled trial in humans has measured laxogenin’s effect on muscle protein synthesis, body composition, or strength compared to a placebo. The entire evidence base for its muscle-building effects in people is essentially anecdotal.
What Lab Research Shows
The limited scientific research on laxogenin comes from cell-based (in vitro) experiments, not human trials. A study published in Archives of Toxicology tested the compound’s ability to interact with androgen receptors, the same receptors that testosterone activates to drive muscle growth. The results were mixed. In one type of assay using yeast cells, laxogenin showed zero androgenic activity. In a second assay using human prostate cancer cells, it activated the androgen receptor in a dose-dependent way, but with a twist: at lower concentrations, it actually blocked the receptor, while at higher concentrations it activated it.
When researchers added an androgen receptor blocker to the experiment, laxogenin’s effects were neutralized. This confirmed that the compound does bind to the androgen receptor in human cells. But activating a receptor in a petri dish is a long way from building muscle in a living person. The study’s own authors noted that further investigation into any actual anabolic (muscle-building) effects is still needed.
This is an important point. If laxogenin does interact with androgen receptors, it may not be as “hormone-free” as supplement companies claim. The research is far too early to say whether it would affect testosterone levels, suppress natural hormone production, or cause other hormonal side effects, but the marketing claim that it has zero hormonal activity is not established science.
Bioavailability and Dosing
Even setting aside whether laxogenin works, there are real questions about how much of it your body actually absorbs when taken as a pill. No published human pharmacokinetic study (measuring how the compound moves through and is processed by the body) exists for 5-alpha-hydroxy-laxogenin specifically. Patent filings for related spirostane compounds suggest they may have a longer half-life than some other plant steroids, with a structurally similar compound showing a roughly 14-hour half-life in rats. But rat data on a related molecule is a very loose foundation for human dosing recommendations.
Supplement companies typically recommend 75 to 150 mg per day, split into three to six doses taken with food. Cycle lengths of three to four months are common in bodybuilding circles. These dosing guidelines are based on user experience and manufacturer recommendations, not clinical research establishing an effective dose range.
Safety Is Largely Unknown
Because no human clinical trials have been conducted, the safety profile of laxogenin is essentially uncharacterized. There is no published data on its effects on liver enzymes, lipid levels, kidney function, or hormonal markers in people. The cell-based research showing androgen receptor activity raises the possibility of hormonal side effects, but this hasn’t been tested in a living system.
The absence of reported side effects in online reviews is not the same as evidence of safety. Many compounds that interact with androgen receptors carry risks that only become apparent with blood work or over longer time periods. Without formal toxicology studies, you’re taking the compound with no real understanding of what it might do to your body beyond what you see in the mirror.
FDA and Legal Status
The FDA placed 5-alpha-hydroxy-laxogenin on its Dietary Supplement Ingredient Advisory List in October 2019, a public signal that the agency does not consider it a lawful supplement ingredient. The advisory list exists specifically to warn consumers about ingredients that may not meet the legal definition of a dietary supplement.
In 2022, the FDA followed up with enforcement action, issuing a warning letter to at least one supplement company selling products containing laxogenin. The letter stated plainly that 5-alpha-hydroxy-laxogenin is not a dietary ingredient under federal law, and that products containing it are adulterated and cannot be legally sold in the United States. Despite this, laxogenin products remain widely available online and in supplement stores. The supplement industry is large, and FDA enforcement is often slow to reach every product on the market.
The Bottom Line on Laxogenin
Laxogenin is a synthetic steroid marketed with strong muscle-building claims that have no support from human research. The only peer-reviewed evidence shows it can activate androgen receptors in a lab dish, which contradicts the popular claim that it has no hormonal effects. No one has measured whether it actually builds muscle in people, what dose would be needed, or what side effects it carries. The FDA considers it an unlawful supplement ingredient. If you’re evaluating it as a training supplement, you’re weighing unverified upside against genuinely unknown risk.