Laxogenin is not a SARM. The two belong to entirely different chemical families, act through different biological pathways, and have very different profiles of evidence behind them. SARMs are synthetic drugs designed to bind the androgen receptor in a tissue-selective way, while laxogenin (more precisely, the supplement ingredient 5α-hydroxy-laxogenin) is a spirostane-type steroid related to plant brassinosteroids. The confusion is understandable, since both are marketed to fitness enthusiasts as muscle-building compounds, and supplement retailers sometimes blur the line deliberately. But the pharmacology, the regulatory status, and the actual research tell two sharply different stories.
What SARMs Actually Are
SARMs, or selective androgen receptor modulators, are synthetic compounds engineered to activate the androgen receptor in certain tissues while leaving others relatively unaffected. The androgen receptor is the same receptor that testosterone and other androgens bind. Traditional anabolic steroids activate this receptor across the body, which is why they build muscle but also cause side effects in the prostate, liver, skin, and cardiovascular system. SARMs were developed to get around that problem: the goal was a molecule that would promote beneficial effects of androgens in target tissues like muscle and bone with greatly reduced unwanted side effects.1PubMed Central. Development of selective androgen receptor modulators (SARMs)
Several SARMs have entered clinical trials. Ostarine (enobosarm) has gone through the most extensive testing, with phase 2 trials showing increases in lean body mass in cancer patients experiencing muscle wasting. LGD-4033 demonstrated dose-proportional gains in lean mass and leg press strength in a small trial in healthy men. MK-0773 was tested in older women and showed increased lean mass over six months but no improvement in strength or physical function.2PubMed Central. Selective Androgen Receptor Modulators as Function Promoting Therapies Despite those lean-mass results across multiple phase 2 trials, convincing improvements in physical function and muscle strength have remained elusive, and long-term outcomes still need to be assessed.3PubMed. Selective androgen receptor modulators (SARMs) as pharmacological treatment for muscle wasting in ongoing clinical trials
No SARM has been approved by the FDA for any medical use. They are not legal dietary supplements. They are investigational drugs that happen to be widely sold online as supplements, which is a regulatory problem rather than a scientific classification.
What Laxogenin Is and Where It Comes From
The ingredient sold in supplements is typically labeled as “5α-hydroxy-laxogenin” or simply “laxogenin.” These are not the same compound, though the terms get used interchangeably by the supplement industry. Laxogenin itself is a naturally occurring compound found in certain Smilax and Allium plant species. However, 5α-hydroxy-laxogenin, the version that actually appears in supplements, has no confirmed natural source. Research has shown that the 5α-hydroxy-laxogenin detected in dietary supplements is synthetic in origin, likely manufactured from diosgenin, a common plant-derived precursor used in steroid drug production.4PubMed Central. Androgenic properties of the dietary supplement 5α-hydroxy-laxogenin
Structurally, 5α-hydroxy-laxogenin belongs to a class called spirostane steroids. It looks somewhat like a steroid on paper because it has a steroidal backbone, which is probably part of why it gets lumped in with SARMs and anabolic steroids in supplement marketing. But “steroid” is a huge structural category that includes everything from cholesterol to cortisol to plant hormones. Having a steroidal structure does not mean a compound acts on the androgen receptor or behaves like testosterone.
Why Laxogenin Does Not Work Like a SARM
The core distinction comes down to the receptor each compound targets. SARMs are defined by their interaction with the androgen receptor. Laxogenin does not meaningfully interact with that receptor in living organisms. When researchers docked 5α-hydroxy-laxogenin into the androgen receptor using computer modeling, the molecule was unable to form a key hydrogen bond with a specific amino acid (Asn705) that genuine androgen receptor ligands need to make. Its oxygen atoms can only accept hydrogen bonds, not donate them the way a true androgen receptor activator would.5PubMed Central. Effects of the Dietary Supplement 5α‐Hydroxy‐Laxogenin in the Orchiectomized Rat Model
That molecular detail matters because it translates into a real-world result: when researchers gave 5α-hydroxy-laxogenin to castrated rats at three different dosages over two weeks, it produced no effect on androgen-sensitive tissues like the prostate or seminal vesicles, and no anabolic effect on muscle tissue. At the highest dose tested, some target tissues actually showed greater atrophy than in untreated animals. In short, the compound showed neither androgenic nor anabolic activity in a standard animal model designed to detect exactly those effects.5PubMed Central. Effects of the Dietary Supplement 5α‐Hydroxy‐Laxogenin in the Orchiectomized Rat Model
If laxogenin has any muscle-related activity, the hypothesis in the research literature points toward a completely different pathway. Brassinosteroids, the broader plant hormone family that laxogenin is related to, have been shown to stimulate protein synthesis and inhibit protein breakdown in rat muscle cells through the PI3K/Akt signaling pathway.6PubMed Central. Anabolic effect of plant brassinosteroid This is a growth-signaling pathway that many cell types use and that has nothing to do with the androgen receptor. Research on synthetic brassinosteroid derivatives has confirmed that these compounds selectively activate PI3K/Akt signaling, leading to increased Akt phosphorylation in cell cultures.7PubMed Central. Akt-dependent anabolic activity of natural and synthetic brassinosteroids in rat skeletal muscle cells
There is a big gap between those cell-culture findings and what happens in a living human body, though. The brassinosteroid research showed effects in isolated rat muscle cells. When 5α-hydroxy-laxogenin itself was tested in live animals, it failed to produce any measurable muscle growth. The connection between the broader brassinosteroid family’s activity in a petri dish and laxogenin’s practical utility as a supplement remains unproven.
The Evidence Gap for Laxogenin
One of the starkest differences between laxogenin and SARMs is the quantity and quality of human evidence. SARMs have been through multiple phase 1 and phase 2 clinical trials involving hundreds of participants. Those trials have measurable outcomes: changes in lean body mass, bone density, hormone levels, liver markers. The results are mixed but they exist, and they have been published in peer-reviewed journals.
Laxogenin has essentially none of that. As of the most recent research, evidence is missing on any anabolic or androgenic activity of 5α-hydroxy-laxogenin in humans.4PubMed Central. Androgenic properties of the dietary supplement 5α-hydroxy-laxogenin No published clinical trial has tested whether laxogenin supplements produce muscle growth, strength gains, fat loss, or any other outcome in people. The marketing claims are built almost entirely on the brassinosteroid cell-culture studies and on anecdotal user reports, neither of which counts as evidence that a supplement works. Since 2019, 5α-hydroxy-laxogenin has been included on the FDA’s dietary supplement ingredient advisory list, which flags ingredients that may not meet the legal definition of a dietary supplement ingredient.
Supplement Adulteration and Quality Problems
Even if you decided to try laxogenin supplements, there is a serious question of whether you would actually be getting what the label says. An analysis of twelve dietary supplements labeled as containing 5α-hydroxy-laxogenin or laxogenin found that five of them contained no 5α-hydroxy-laxogenin at all. The remaining seven contained the labeled ingredient but were also contaminated with various spirostane-type compounds that were not listed on the label. Several synthetic derivatives of diosgenin showed up uninvited. One product even contained arimistane, an actual anabolic androgenic steroid and aromatase inhibitor, completely unlabeled. And none of the twelve products contained laxogenin itself, the natural plant compound, in any detectable amount.8PubMed. The power of hyphenated chromatography-Time of flight mass spectrometry for unequivocal identification of spirostanes in bodybuilding dietary supplements
This finding underscores a problem that goes beyond laxogenin. It means you cannot assume a laxogenin product contains laxogenin, and you cannot assume it is free of genuinely hormonal contaminants. The presence of unlabeled arimistane is particularly concerning because that compound actually does affect estrogen metabolism and could cause real endocrine side effects. A person buying a “natural plant anabolic” could unwittingly be taking a hormonal drug.
This adulteration issue also muddies any anecdotal evidence. If some users report muscle gains or strength improvements from laxogenin products, and those products contain unlabeled anabolic compounds, the perceived benefits may have nothing to do with laxogenin itself.
How SARMs Affect Hormones (and Why Laxogenin Probably Does Not)
One of the defining characteristics of SARMs is their effect on the hormonal axis. Because SARMs activate the androgen receptor, the body detects elevated androgenic signaling and reduces its own testosterone production in response. In a controlled trial of LGD-4033, researchers observed dose-dependent suppression of testosterone levels and sex hormone binding globulin. At the highest dose tested, free testosterone levels dropped measurably after just 21 days.9PubMed Central. Selective Androgen Receptor Modulators (SARMs) – Current Knowledge and Clinical Applications This is one of the main reasons SARMs require post-cycle recovery protocols similar to those used with anabolic steroids: they disrupt your natural hormonal balance.
Laxogenin, based on the available animal evidence, does not activate the androgen receptor in living organisms. That means it should not cause testosterone suppression, estrogen-related side effects, or any of the hormonal disruption associated with SARMs or anabolic steroids. Supplement sellers often market this as a selling point: “all the muscle-building benefits with none of the hormonal side effects.” The problem with that framing is that it implies there are muscle-building benefits in the first place, which has not been demonstrated.
SARM Safety Concerns Worth Knowing About
Because SARMs are often discussed alongside laxogenin in supplement communities, it is worth understanding what the actual risks of SARMs look like. The most prominent safety issue that has emerged is liver damage. Since 2020, at least 20 published reports have described adverse events, most involving drug-induced liver injury, in people using SARM-containing supplements. The typical presentation involved cholestatic or hepatocellular liver injury and jaundice.10PubMed Central. Selective androgen receptor modulator use and related adverse events including drug-induced liver injury: Analysis of suspected cases SARMs can disrupt normal liver function through oxidative stress, changes in lipid metabolism, and direct toxicity to liver cells.11PubMed Central. Silent Threats to the Liver: Acute Hepatotoxicity Attributed to Selective Androgen Receptor Modulators (SARMs)
An important caveat is that dosage and purity data in these case reports are limited. People buying SARMs from supplement vendors are rarely getting pharmaceutical-grade products, and the actual content may not match the label. This makes it hard to separate the toxicity of the SARM itself from the toxicity of whatever else was in the bottle. Still, the pattern of liver injury is consistent enough to be a genuine concern.
SARMs have also shown effects on blood lipids and liver enzymes in clinical trials. In the MK-0773 trial in older women, participants receiving the drug experienced modest increases in liver transaminase levels and decreases in HDL cholesterol.2PubMed Central. Selective Androgen Receptor Modulators as Function Promoting Therapies Women in that trial did not show overt androgenic side effects like acne or excess hair growth, but the metabolic markers raised flags.12PubMed Central. Selective Androgen Receptor Modulators in Women: What Do We Know, and What Is Still Missing
A Side-by-Side Comparison
For clarity, here are the key differences between the two compounds laid out directly:
- Chemical class: SARMs are synthetic non-steroidal or steroidal compounds designed to bind the androgen receptor. 5α-hydroxy-laxogenin is a synthetic spirostane steroid related to plant brassinosteroids.
- Receptor target: SARMs bind and activate the androgen receptor in a tissue-selective manner. Laxogenin does not activate the androgen receptor in living animals.
- Proposed mechanism: SARMs mimic androgen signaling. Brassinosteroids (laxogenin’s broader family) may act through the PI3K/Akt protein synthesis pathway, but this has only been shown in cell cultures, not in whole-animal or human studies for laxogenin specifically.
- Human clinical trials: SARMs have been through multiple phase 1 and 2 trials. Laxogenin has none.
- Hormonal suppression: SARMs suppress natural testosterone production in a dose-dependent manner. Laxogenin is not expected to, based on its lack of androgen receptor activity.
- Regulatory status: SARMs are unapproved investigational drugs. 5α-hydroxy-laxogenin is flagged on the FDA’s dietary supplement ingredient advisory list.
- Known risks: SARMs carry documented risks of liver injury, lipid changes, and hormonal disruption. Laxogenin’s risk profile is largely unknown due to the absence of clinical data, though the adulteration of commercial products introduces its own hazards.
Why the Confusion Persists
The supplement industry has every incentive to blur these categories. Calling something a “natural SARM alternative” or a “plant-based anabolic” taps into the interest in SARMs while sidestepping their legal and safety baggage. Laxogenin fits that marketing niche perfectly because it has a steroidal chemical structure, it is loosely related to compounds that showed anabolic potential in cell studies, and it has not been studied enough for anyone to definitively say it does not work in humans.
That last point is subtle but important. Absence of evidence is not evidence of absence, and supplement marketers exploit that gap aggressively. The honest summary is that 5α-hydroxy-laxogenin failed to show any muscle-building effect in the one in vivo study that tested it, it cannot properly bind the androgen receptor the way it would need to in order to function like a SARM, and no one has published a single controlled human trial on it. Calling it a SARM is not just inaccurate; it misrepresents the biology at every level.
Adulteration as the Hidden Variable
Perhaps the most practically relevant takeaway is that the laxogenin supplement you buy may not contain laxogenin at all, and it may contain compounds that are genuinely hormonal. The analytical study that found arimistane in a laxogenin-labeled product illustrates a scenario where a consumer thinks they are taking a mild, non-hormonal plant extract and is actually ingesting an aromatase inhibitor that could suppress estrogen production and cause side effects including joint pain, mood changes, and disrupted lipid profiles.8PubMed. The power of hyphenated chromatography-Time of flight mass spectrometry for unequivocal identification of spirostanes in bodybuilding dietary supplements
This is not unique to laxogenin products. The bodybuilding supplement market has a well-documented history of including undeclared pharmaceutical ingredients, and products marketed as “natural” or “plant-based” are not exempt. If you are considering any supplement sold for physique or performance purposes, especially one that claims steroid-like results without steroid-like side effects, third-party batch testing from an independent lab is the minimum due diligence. Without it, you are trusting a label that analytical chemistry has repeatedly shown to be unreliable.