Natural Anabolics Explained: A Guide to Ecdysteroids, Phytoecdysones, and SARM-Like Compounds

Information

This guide covers compounds used in dietary supplements for healthy adults (18+). It does not replace a balanced diet or physician-prescribed medication. Some compounds discussed (SARMs, prohormone-class methylated anabolics) are sold as advanced supplements or research chemicals for informed athletes — not as everyday dietary supplements — and have varying legal status across the EU.

Before adding any anabolic-class supplement, check your training consistency and caloric balance, whether you're taking medications that may interact (statins, anticoagulants, hepatotoxic drugs), and your baseline bloodwork (liver enzymes, lipid panel, total and free testosterone). If in doubt — consult a physician or licensed pharmacist.
Read the full Safety FAQ →

Year 4 of lifting. The PRs you set in year 2 still feel respectable, but the bar speed on a heavy 5×5 has gone from "moves" to "grinds." Whey is dialled in, creatine is loaded year-round, sleep is mostly eight hours, programming is Russian-block-style periodisation that you actually follow. The scale moved 4 kg in year 1, 3 kg in year 2, 2 kg in year 3 — and now it's been parked at the same number for nine months. The mirror agrees with the scale.

You start scrolling. "Turkesterone — the natural anabolic that actually works." "Ecdysterone vs steroids — closer than you think." "5α-hydroxy laxogenin — the legal mass agent." The forum threads run hot in both directions: some lifters post N=1 transformations that look real, others say the entire class is a marketing fabrication. The studies, when you actually click through, range from "one decent human RCT" to "zero published human data, three rodent papers, a lot of in vitro." The marketing copy is more confident than the literature.

This guide is the framework for thinking about that whole class without getting played by either side. Natural anabolics are tools with specific mechanisms, specific evidence levels, and specific use cases. They sit on top of training, calories, sleep, and hormonal status — not in place of any of them. The informed athlete uses them for what they are: ergogenic aids that, in the right context, contribute meaningfully to a hypertrophy block.

What "Natural Anabolic" Actually Means

The phrase gets stretched in marketing copy until it loses content. A working definition with sharp edges:

A natural anabolic is a compound — typically plant-derived — that exerts an anabolic effect on skeletal muscle through a mechanism distinct from direct androgen receptor agonism, and which is not classified as a controlled anabolic-androgenic steroid (AAS).

That definition lets in three categories — and rules out one that marketing copy often smuggles in.

Category	What it includes	Mechanism family	Belongs here?
Ecdysteroids	Beta-ecdysterone (ecdysterone), turkesterone	ERβ agonism, mTOR signalling	Yes
Phytosteroid analogues	5α-hydroxy laxogenin	Speculative non-AR pathway	Yes (with caveats)
SARM-like compounds	RAD-140, LGD-4033, Ostarine, S-23	Tissue-selective AR agonism	No — research chemicals, not natural
Methylated prohormones	Epistane, M-Sten, Halodrol	Direct AR agonism + hepatotoxicity	No — oral anabolic compounds, not "natural" anything

Two clarifications worth making before going further.

First, SARMs are not natural anabolics. They bind the androgen receptor directly (like testosterone does), they have substantial human pharmacokinetic data from clinical trials, they suppress the HPTA, and they are sold in the EU as research chemicals (RUO — Research Use Only). Marketing that groups them with ecdysteroids under the same "legal anabolic" umbrella is conflating categories that have different mechanisms, different evidence bases, and very different risk profiles. We treat SARMs separately and with the regulatory respect that classification demands.

Second, prohormones are categorically not natural anabolics. Compounds like Epistane, M-Sten, or Halodrol are methylated oral anabolic-androgenic compounds. They suppress endogenous testosterone, they stress the liver, they require post-cycle therapy, and they belong on Pillar II's territory — not here. If a "natural anabolic" stack includes a methylated compound on the label, the marketing is dishonest.

This article focuses on the ecdysteroid class and the phytosteroid analogue laxogenin — the compounds you can actually run as supplements in most EU jurisdictions, with the most defensible "advanced beyond basics" use case. SARMs get covered in their section below, with the regulatory framing they require.

The Mechanism Layer: How Ecdysteroids Are Supposed to Work

Ecdysteroids are insect moulting hormones. They appear in plants like Ajuga turkestanica (the source of turkesterone), Rhaponticum carthamoides (Russian leuzea, a source of ecdysterone), and ordinary spinach (also ecdysterone, at lower concentrations) at levels high enough to extract commercially. Their proposed anabolic mechanism in vertebrates rests on three pillars.

1. ERβ (estrogen receptor beta) agonism

Ecdysterone has been shown in vitro to bind ERβ — an estrogen receptor subtype expressed in skeletal muscle and associated with hypertrophy signalling without the feminising effects of ERα stimulation. A 2015 Biology of Sport review by Parr et al. characterised ecdysterone as a non-conventional anabolic agent acting through ERβ-mediated pathways¹. The ERβ pathway is anabolic in muscle but does not produce gynaecomastia, water retention, or HPTA suppression — which is the mechanistic argument for why ecdysteroids occupy a different space from anabolic-androgenic steroids.

2. mTOR pathway activation

Cell-culture work by Gorelick-Feldman et al. (2008) showed phytoecdysteroids — including beta-ecdysterone — increased protein synthesis in skeletal muscle cells via Akt/mTOR-related signalling². This is the central hub of muscle protein synthesis. Whether the in vitro signal translates to a clinically meaningful hypertrophy effect at typical oral doses in humans is the question that the in vivo evidence has to answer.

3. Increased leucine incorporation into muscle protein

Older Soviet and Russian research on ecdysterone reported increased nitrogen retention and amino acid incorporation in trained athletes. The methodological quality of this work varies — much of it predates modern reporting standards — but the directional signal aligns with the in vitro mechanism.

The problem with that list isn't the mechanisms themselves. It's the gap between in vitro plausibility and in vivo human evidence in the typical lifter. A compound can be mechanistically plausible at the cell-culture level and still fail to produce a measurable effect in trained men. The literature has to do that work.

Pharmacological Perspective

Ecdysteroids do not bind the androgen receptor and do not suppress the HPTA. They do not require post-cycle therapy. They are well-tolerated in studies to date, with no consistent reports of hepatotoxicity, lipid disturbance, or hormonal dysregulation in healthy adults at typical oral doses (200-1000 mg per day for ecdysterone; 250-750 mg per day for turkesterone). They are not equivalent to anabolic-androgenic steroids in either effect size or risk profile. Marketing that suggests otherwise is dishonest. Combining with hepatotoxic medications has not been formally studied.

Evidence Ranking: From "Defensible Human RCT" to "Almost Entirely Marketing"

Here is the landscape, ranked honestly. This is the table you would build if you actually read the literature instead of reading product copy.

Compound	Strongest human evidence	Evidence tier	What that means
Beta-ecdysterone	Isenmann et al. 2019 — 10-week RCT in trained men, significant fat-free mass and bench press gains vs placebo3	A — best in class	One well-designed human RCT plus consistent mechanism. WADA placed ecdysterone on the monitoring list partly on the strength of this signal.
Turkesterone	Mostly rodent and in vitro; no robust independent human RCT to date	C — plausible by analogy	Same plant family, similar mechanistic story, but human evidence is anecdotal abundance and controlled-trial scarcity. Wilborn et al. 2006 looked at ecdysterone (not turkesterone) and found no effect — relevant context6.
5α-hydroxy laxogenin	Effectively zero published human RCTs; mechanism speculative	D — weak evidence base	Heavily promoted in the US hardcore supp scene; the published human data is sparse and underwhelming.
HMB	Multiple RCTs; effects strongest in untrained populations and during caloric restriction	B — modest, context-dependent	Earns a place in the supporting cast (cutting phases, novices) more than as a primary mass agent7.
SARMs	Phase I/II clinical trial data exists	Research chemical, not natural	Substantial human PK data, but from medical research — not supplement trials. Suppress HPTA, require PCT.

The honest reading: ecdysterone has the best human evidence in the entire ecdysteroid class. If you are going to run one ecdysteroid based on what is actually published, this is the one. Turkesterone has higher name recognition and a thinner evidence base. Laxogenin sits in the murkiest part of the spectrum — high promotional volume, light data.

This is not a takedown of turkesterone. The mechanism is plausible, the rodent data is directionally positive, and athlete reports are abundant enough to suggest something is happening. It is, however, a correction of the marketing-implied evidence ranking. Turkesterone is promising, not proven. Ecdysterone is closer to proven.

A Closer Look at the Three Workhorses

Beta-ecdysterone (ecdysterone)

Source: Rhaponticum carthamoides (Russian leuzea), spinach, Cyanotis arachnoidea. Mechanism: ERβ agonism + mTOR activation in skeletal muscle. Best human study: Isenmann et al. (2019) — 46 trained young men, randomised, 10 weeks of resistance training with either ecdysterone or placebo. The ecdysterone group showed significantly greater gains in fat-free mass and bench press strength³. Effect size for fat-free mass was approximately 1.5 kg above placebo. Typical oral dose: 200-1000 mg per day. Cycle length: 8-12 weeks, then a 4-week break. No PCT required.

The honest read: Of all the compounds in the natural anabolic category, ecdysterone has the most defensible "evidence-based" claim. The Isenmann RCT is well-designed, the mechanism is plausible, and WADA's interest is itself a signal. The effect size is meaningful but not transformative — roughly 1.5 kg of additional fat-free mass over 10 weeks, on top of programming.

Turkesterone

Source: Ajuga turkestanica (a mint-family plant native to Central Asia). Mechanism: Same ecdysteroid family as beta-ecdysterone; in vitro and rodent work suggests similar ERβ/mTOR pathway activity. Best human study: None of equivalent quality to Isenmann 2019. The human literature is largely athlete reports, smaller open-label work, and extrapolation from rodent data. Typical oral dose: 250-750 mg per day. Bioavailability concerns have led some manufacturers to combine turkesterone with cyclodextrins or other absorption enhancers. Cycle length: 8-12 weeks, then a 4-week break. No PCT required.

The honest read: Turkesterone is the most-marketed compound in the natural anabolic category and the one with the worst evidence-to-marketing ratio. That does not mean it does nothing — the mechanistic story is similar to ecdysterone, the safety profile in healthy adults appears benign, and the rodent data is directionally positive. It does mean that expectations should be calibrated to the data, not the marketing. If a sales page promises ecdysterone-tier results from turkesterone based on the same mechanism, treat that promise with the scepticism it deserves until independent human RCTs catch up.

5α-hydroxy laxogenin

Source: Smilax sieboldii (Asian smilax root) — sometimes labelled "laxogenin" or "laxosterone". Mechanism: Speculative. Marketing copy frequently invokes "anabolic-to-catabolic ratio modulation," a phrase that has roughly the precision of "natural energy support." Best human study: Effectively zero published peer-reviewed human RCTs. Typical oral dose: 50-100 mg per day, often in stack products. Cycle length: 6-8 weeks per typical product label.

The honest read: Laxogenin sits in the part of the natural anabolic category where evidence has not caught up to marketing — and may not. It might do something. The published human data does not currently support the claims made for it. An informed athlete can run it as a curiosity layer; an informed athlete should not run it as the primary anabolic agent in a 12-week mass block.

SARMs: An Important Distinction

SARMs (Selective Androgen Receptor Modulators) — RAD-140 (testolone), LGD-4033 (ligandrol), MK-2866 (ostarine), S-23, S-4 (andarine) — are not natural anabolics. They are synthetic small molecules that bind the androgen receptor with tissue-selective activity, originally developed by pharmaceutical companies for muscle-wasting and bone-density indications. The category gets pulled into "natural anabolic" guides because the marketing framing is similar — "anabolic, but legal/safer/non-suppressive" — but the underlying pharmacology is fundamentally different.

Regulatory Status — SARMs

SARMs are sold in the EU as research chemicals (RUO — Research Use Only). They are not registered as medicinal products and not authorised as food supplements. They are not intended for human consumption in a medical context. The studies presented for SARMs are educational material — not clinical recommendations. SARMs do suppress endogenous testosterone production. SARMs do require post-cycle therapy. SARMs have a real adverse event profile including lipid alterations (HDL suppression), transient liver enzyme elevations, and HPTA suppression that can take months to resolve. Consultation with a physician is required if you are considering use. SARMs are prohibited in WADA-tested sport. Safety FAQ →

The categorical differences between SARMs and ecdysteroids are significant:

1. HPTA suppression. SARMs suppress endogenous testosterone (LGD-4033 in particular has documented suppression at low doses⁵). Ecdysteroids do not. SARMs require structured PCT; ecdysteroids do not.
2. Effect size. A run of LGD-4033 at 5-10 mg per day for 8 weeks will produce substantially more muscle accrual than 500 mg of ecdysterone over the same period — and substantially more side-effect risk. The two are not directly comparable.
3. Regulatory framing. Ecdysteroids are sold as supplements in most EU jurisdictions. SARMs are research chemicals. Buying, possessing, and using each carries different legal context country by country.

If you are considering SARMs, the framing isn't "are these stronger natural anabolics?" — it's do you understand you're using research chemicals with hormonal effects, and have you set up the bloodwork, the cycle support, and the PCT protocol to do it responsibly? That conversation belongs in Pillar II: Testosterone, PCT & Cycle Support, not here.

Side-Effect and Safety Profile Across the Class

Stacking compounds means stacking risk. Here is what the literature and clinical reporting support across the natural anabolic class.

Compound	Hepatotoxicity	HPTA suppression	Cardiovascular
Ecdysterone	None reported in published human work	None — does not bind AR	Neutral; some animal data suggests mild blood pressure benefits
Turkesterone	None reported (limited data)	Not reported	Not reported as a concern
Laxogenin	Anecdotal reports of liver enzyme elevation; mechanism unclear	Not reported	Not reported
HMB	Not reported as hepatotoxic	None	Neutral7
SARMs (research chemicals)	Transient AST/ALT elevations reported in clinical trials	Yes — significant	HDL reductions documented

The headline reading: ecdysteroids are pharmacologically the safest layer in the natural anabolic category at typical doses in healthy adults. SARMs are categorically different on every safety axis. Laxogenin's safety profile is harder to characterise because the underlying mechanism is poorly understood — and a poorly understood mechanism is harder to monitor for off-target effects.

From the athlete's perspective — Cedric Preston

"The lifters I coach who get the most out of ecdysteroids share three habits: they only run them inside a real hypertrophy block, not casually year-round; they're already in a 200-300 kcal surplus; and they treat the supplement as the third or fourth variable — protein, training, sleep first; then creatine; then the ecdysteroid. Run in that order, the gains are real and measurable. Run as the lead variable on top of mediocre training, the gains are imaginary. The compound rewards the system, not the molecule."

How Natural Anabolics Fit Into a Mass Block

Natural anabolics are the third or fourth lever you pull. They work on top of a complete mass infrastructure — not in place of it.

The non-negotiables

These earn their place in any mass phase, regardless of whether you run an ecdysteroid on top:

• Protein: 1.6-2.2 g/kg bodyweight per day, dosed across 4-5 meals
• Creatine monohydrate: 3-5 g per day, year-round (the single best-evidenced ergogenic in the entire category)⁴
• Beta-alanine: 3.2-5 g per day, chronic loading, for high-rep accessory work⁸
• Sleep: 7.5-9 hours, structured. This is more anabolic than any compound in this article.

If those four are not consistent, no ecdysteroid is going to fix the deficit.

The training intensity layer

A pre-workout matched to the session keeps training intensity high through the back half of a 10-12 week mass block — the period during which most lifters' programmes degrade. The intensity drives the stimulus; the stimulus drives the response. For the framework, see Pillar I: Advanced Pre-Workout Guide.

The natural anabolic layer

A defensible 10-week ecdysterone protocol: 500 mg ecdysterone per day, dosed split (250 mg AM with breakfast, 250 mg with pre-training meal). Pair with vitamin D3 (2000-4000 IU) and magnesium (300-400 mg elemental) — both support testosterone optimisation in deficient lifters and improve sleep quality. After week 10: 4 weeks off, then assess with bloodwork and body composition.

If you run turkesterone instead: 500-750 mg per day, same dosing structure, same break schedule. Calibrate expectations to the thinner evidence base — adjust your expectations for outcome size downward by roughly 30-40% versus an ecdysterone protocol of equivalent length. For the full periodised protocol, see The Advanced Mass Stack: a 12-Week Protocol (forthcoming).

Realistic expectations

A reasonable expectation for a well-designed ecdysterone protocol over 10 weeks in a trained lifter, on top of programming and a 200-400 kcal surplus, is 0.5-1.5 kg additional lean mass and 5-15 kg added across compound lifts beyond what programming alone would produce³. That is meaningful. It is not transformative. The lifter who runs turkesterone hoping to add 5 kg of lean mass in 8 weeks is going to be disappointed and is going to conclude "natural anabolics don't work" — which is the wrong conclusion drawn from the wrong expectations.

What to Track: Bloodwork and Body Composition

Natural anabolics are well-tolerated in healthy adults at typical doses, but a 10-week mass block produces enough physiological change that monitoring is reasonable. Track total and free testosterone (pre-, mid-, post-block — predicts response), a lipid panel and liver enzymes (pre and post — verify what's actually in any "mass-building blend"), body composition by DXA or BIA (distinguishes lean from fat mass), and standing waist circumference weekly (cheap proxy for visceral fat during a surplus). A lifter who measures these is operating on a different plane from the lifter scrolling Reddit asking "is my turk working?" We don't guess on this stuff — we measure.

Inter-Pillar Bridge: Where This Layer Fits

Natural anabolics work within a window defined by three other pillars. Pull one out, the layer underperforms.

Testosterone is the ceiling. Your hormonal milieu sets the upper bound on muscle protein synthesis. A lifter at 800 ng/dL total testosterone gains mass faster than the same lifter at 400 ng/dL, on the same programme. No ecdysteroid raises that ceiling — they amplify what the ceiling allows. If your bloodwork shows total testosterone in the lower third of the reference range, the highest-leverage move is whatever moves your testosterone higher in a healthy way: sleep, body fat in the 10-15% range for men, sufficient zinc and magnesium, and where appropriate a natural test booster stack with fadogia agrestis and tongkat ali. Those protocols live in Pillar II: Testosterone, PCT & Cycle Support.

Recovery is the floor. A 10-week mass block at high training volume is a recovery problem first, a stimulus problem second. If sleep degrades, joints accumulate inflammation, and CNS fatigue compounds, the block ends with diminishing returns by week 6 — regardless of what compound you layered on top. Sleep architecture, joint support, and recovery infrastructure live in Pillar V: Recovery & Athlete Longevity (forthcoming). Without recovery, every other pillar performs at 60%.

Training intensity drives the stimulus. No stimulus, no response. The pre-workout architecture that keeps intensity high across a mass block lives in Pillar I: Advanced Pre-Workout Guide.

Conclusion

Natural anabolics are real tools with real (if modest) effects in a context that supports them. They are not steroids. They are not miracle compounds. They are not interchangeable — ecdysterone has earned its place in the literature in a way turkesterone has not yet, and laxogenin has not at all. SARMs sit in a different category and deserve their own conversation.

The informed athlete treats the basics (protein, creatine, sleep, training consistency) as non-negotiable; picks ecdysterone over turkesterone when evidence quality matters more than marketing volume; treats SARMs and prohormones as separate categories with separate rules, not "stronger natural anabolics"; runs cycles, not perpetual use; and measures bloodwork and body composition before and after every block. Natural anabolics reward the system, not the molecule. Build the system first.

Read the full Pillar III guide: Natural Anabolics for Mass Gain — forthcoming.
Browse the Mass Up category →

References

1. Parr MK, Botrè F, Naß A, et al. (2015). Ecdysteroids: A novel class of anabolic agents?. ↩
2. Gorelick-Feldman J, Maclean D, Ilic N, et al. (2008). Phytoecdysteroids increase protein synthesis in skeletal muscle cells. ↩
3. Isenmann E, Ambrosio G, Joseph JF, et al. (2019). Ecdysteroids as non-conventional anabolic agent: performance enhancement by ecdysterone supplementation in humans. ↩
4. Kreider RB, Kalman DS, Antonio J, et al. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation. ↩
5. Basaria S, Collins L, Dillon EL, et al. (2013). The safety, pharmacokinetics, and effects of LGD-4033, a novel nonsteroidal oral, selective androgen receptor modulator, in healthy young men. ↩
6. Wilborn CD, Taylor LW, Campbell BI, et al. (2006). Effects of methoxyisoflavone, ecdysterone, and sulfo-polysaccharide supplementation on training adaptations in resistance-trained males. ↩
7. Wilson JM, Fitschen PJ, Campbell B, et al. (2013). International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB). ↩
8. Trexler ET, Smith-Ryan AE, Stout JR, et al. (2015). International Society of Sports Nutrition position stand: Beta-alanine. ↩