🧬 SARMS vs Prohormones (With Dr. Helen Morris, PhD)

For decades, the pursuit of stronger muscles, better recovery, and enhanced performance has led athletes and researchers alike to study compounds that influence the body’s anabolic pathways. While anabolic steroids and prohormones have long dominated that conversation, a new class of compounds — Selective Androgen Receptor Modulators (SARMs) — has taken center stage in research circles.

But what exactly makes SARMs different? Are they safer, more selective, or just another iteration of performance-enhancing chemistry?
Let’s take a closer look at the molecular, biological, and legal differences between SARMs, steroids, and prohormones — and what that means for scientific research today.

⚗️ The Basics: Three Classes, One Goal

All three — SARMs, steroids, and prohormones — influence the androgen receptor (AR), the key regulator of muscle and bone development. But they interact with it in very different ways.

At first glance, they may seem to have the same outcome — influencing growth, strength, or metabolism — but their molecular precision, side-effect profile, and legal treatment couldn’t be more different.

💪 What Are Steroids?

Anabolic-androgenic steroids (AAS) are synthetic derivatives of testosterone.
They were first developed in the 1930s to treat conditions like muscle wasting and hypogonadism, and later became infamous for their non-medical use in sports and bodybuilding.

How they work:
Steroids enter cells and bind directly to androgen receptors throughout the body — in muscle, prostate, liver, brain, and skin.
This broad activation triggers gene transcription across multiple tissues, leading to both desirable and undesirable effects:

• ✅ Anabolic (muscle-building): increased protein synthesis, nitrogen retention, and muscle hypertrophy.
• ⚠️ Androgenic (hormonal): increased sebum production, hair growth, prostate enlargement, and suppression of natural testosterone.

Because they’re non-selective, steroids affect virtually every tissue that expresses androgen receptors. This is why medical doses for therapeutic use are tightly controlled — and misuse often leads to serious side effects such as:

• Hormonal shutdown
• Liver toxicity (especially with oral compounds)
• Lipid imbalance (lower HDL, higher LDL)
• Cardiovascular stress
• Psychological effects (“roid rage,” mood swings)

In short, steroids are powerful but blunt instruments — they enhance growth, but they activate everything.

⚗️ What Are Prohormones?

Prohormones are precursors — inactive molecules that the body converts into active hormones once ingested.
In the early 2000s, they exploded in popularity as over-the-counter “legal steroid alternatives.”

How they work:
Once consumed, prohormones undergo enzymatic conversion in the liver into anabolic steroids. This means that, biologically, they’re not much different from steroids — just a different delivery route.

Because of this conversion process, they share most of the same risks:

• Hormonal suppression (due to negative feedback)
• Liver strain
• Altered cholesterol and blood pressure
• Gynecomastia (via estrogenic conversion)

Prohormones were eventually banned in the U.S. under the Designer Anabolic Steroid Control Act (2014), and similar restrictions exist across Europe and the UK. Many “supplement” products marketed as prohormones were later found to contain undeclared steroids or analogues, making them legally and medically risky.

🧠 What Makes SARMs Different?

SARMs represent a completely different design philosophy.
Rather than converting to hormones or broadly activating androgen receptors, they’re engineered to bind selectively — targeting specific tissues like muscle and bone while minimizing activation in others such as the prostate, liver, or skin.

Mechanism of Action

SARMs bind to the same receptor as testosterone but cause distinct structural changes in the receptor’s shape. This “selective modulation” means:

• In muscle and bone tissue, they trigger anabolic gene expression.
• In other tissues, they either don’t activate or partially activate the receptor, reducing unwanted side effects.

This concept is similar to how Selective Estrogen Receptor Modulators (SERMs) like tamoxifen act differently in breast and bone tissue.

Examples in Research

The most studied SARMs include:

• Ostarine (MK-2866) – Investigated for muscle wasting and osteoporosis.
• RAD-140 (Testolone) – High AR affinity, preclinical data on muscle and neuroprotection.
• LGD-4033 (Ligandrol) – Studied for lean mass preservation in elderly populations.

These compounds remain investigational only — no SARMs are approved by the FDA, MHRA, or EMA for human or veterinary use.

🧩 Structural and Chemical Differences

This is Ostarine, and compared to 1-Androstenedione:

The molecular structures of steroids, prohormones, and SARMs are markedly different.

SARMs’ nonsteroidal nature is crucial — they’re designed to avoid hepatic metabolism pathways that cause toxicity or hormonal imbalances.
This structural independence is what allows researchers to study tissue selectivity and metabolic stability in greater detail.

⚖️ Comparing Biological Effects

🧬 Why “Selective” Matters in Research

The word selective is the essence of what separates SARMs from the past generation of androgen modulators.
For scientists, this selectivity opens up avenues to:

• Study bone formation without unwanted androgenic effects.
• Investigate muscle regeneration in aging or catabolic conditions.
• Explore neuroprotective pathways influenced by androgen signaling.

This precision is why SARMs have been investigated as potential tools for studying disorders like osteoporosis, cachexia, and sarcopenia, though all remain at the research stage.

🚫 Misuse and Legal Context

While SARMs have gained attention outside laboratories, global health agencies — including the FDA, FSA, and MHRA — have issued clear warnings:

SARMs are not approved for human consumption.
They are research compounds only, intended for laboratory analysis, receptor studies, and non-clinical applications.

In the UK, marketing SARMs as supplements or human-use products violates Food Standards Agency and Trading Standards regulations.
In the US, selling them as dietary supplements contravenes the Food, Drug, and Cosmetic Act.

🧠 Ethical and Scientific Implications

SARMs represent an exciting chapter in androgen research — not as a consumer product, but as a proof of concept for selective receptor modulation.
They demonstrate that it’s possible to design molecules that:

• Retain anabolic activity
• Reduce off-target effects
• Offer new insights into hormonal regulation

However, the field remains preclinical. Long-term safety, receptor desensitization, and metabolic impacts are still under investigation.

As with any emerging science, transparency, peer review, and ethical research practices are key to ensuring that SARMs contribute meaningfully to medicine — not misuse.

An interview between the Max Muscle Labs research team and Dr. Helen Morris, PhD — Pharmacologist, University of Cambridge

MML:

Dr. Morris, thank you for joining us. There’s a lot of public confusion around SARMs, steroids, and prohormones. Could you start by explaining, at a molecular level, how these compounds differ?

Dr. Morris:

Absolutely.
All three categories influence the androgen receptor — that’s the cellular switch controlling muscle and bone growth.
The key difference lies in specificity.

• Steroids are broad-spectrum activators — they bind to androgen receptors everywhere: muscle, prostate, skin, brain.
• Prohormones are precursors — they’re converted inside the body into active steroids, essentially triggering the same pathways.
• SARMs, on the other hand, are designed to be selective. They bind to the receptor but produce distinct structural changes that favor anabolic effects in muscle and bone without heavily activating other tissues.

This is what we mean when we call them “selective modulators.” They act more like precision tools than sledgehammers.

MML:

So, in simple terms, steroids are powerful but non-selective, prohormones are converted versions of those steroids, and SARMs are engineered for precision?

Dr. Morris:

Exactly.
Think of steroids as a floodlight — they illuminate everything in the pathway.
SARMs are like a laser pointer — targeted and programmable.

From a pharmacological standpoint, SARMs use nonsteroidal backbones, meaning they don’t share the same structural core as testosterone. That’s why they generally avoid conversion to estrogen (via aromatase) or dihydrotestosterone (via 5α-reductase) — the two processes responsible for many side effects in steroid use.

MML:

That’s fascinating. How does that selectivity translate in research terms? What makes it valuable for scientists?

Dr. Morris:

Selective modulation allows researchers to isolate tissue-specific effects.
For example, in osteoporosis research, SARMs can be used to study bone formation without affecting the prostate. In cachexia studies, they help evaluate muscle protein synthesis without triggering hormonal imbalances.

This makes SARMs valuable as research probes — tools for understanding receptor behavior, not approved drugs.

MML:

You mentioned steroids can cause broad activation. Could you expand on the biological trade-offs of that?

Dr. Morris:

Of course. When steroids activate androgen receptors everywhere, you get both anabolic (growth-promoting) and androgenic (hormonal) effects.

The anabolic outcomes — like increased protein synthesis and muscle growth — are useful in therapeutic contexts, but the androgenic side effects can include:

• Suppression of natural testosterone
• Hair loss or acne
• Mood changes
• Liver strain (in oral compounds)

This is because the androgen receptor exists in many tissues beyond muscle. The lack of selectivity means you can’t turn one on without triggering others.

SARMs were designed to solve that. By altering receptor conformation, they selectively activate anabolic gene expression in muscle and bone while minimizing the rest.

MML:

So SARMs were designed as a refinement of earlier androgen therapies rather than a replacement?

Dr. Morris:

Exactly.
They were developed in the 1990s by companies like Ligand Pharmaceuticals and GTx Inc.
The goal was to retain the therapeutic benefits of anabolic steroids — such as preserving lean mass in muscle-wasting conditions — while minimizing the androgenic risks.

Even though clinical approval hasn’t yet been achieved, that early research taught us an enormous amount about receptor selectivity, gene expression, and metabolic regulation.

MML:

And how do prohormones fit into this picture?

Dr. Morris:

Prohormones were a sort of middle step between steroids and SARMs — more chemistry than pharmacology.

They’re simply molecules that convert into active steroids inside the body. For example, 1-androstenedione converts into testosterone derivatives after passing through the liver.
The result is the same broad receptor activation — and unfortunately, the same side effects.

Because many of these were sold over-the-counter without proper testing, regulators eventually banned most of them. The Designer Anabolic Steroid Control Act (2014) in the US and similar UK actions closed those loopholes.

MML:

Given that, what do you see as the scientific future of SARMs research?

Dr. Morris:

SARMs have opened up several fascinating research pathways.
We’re now exploring next-generation analogues with even greater receptor precision — molecules that can activate muscle receptors without influencing liver enzymes or reproductive tissues.

Advances in computational chemistry and AI-based receptor modeling allow us to simulate how a new compound will behave before it’s ever synthesized.
That accelerates discovery while reducing unnecessary in vivo testing.

I also see SARMs research merging with gene-editing and biomaterial technologies — for example, using receptor modulators in tissue-engineered scaffolds to promote localized regeneration.

It’s a rapidly evolving field — though still firmly in the preclinical stage.

MML:

And from a regulatory standpoint, what’s the current status?

Dr. Morris:

Regulators are clear: SARMs are not approved for human or veterinary use anywhere in the world.
They’re classified strictly as investigational compounds for laboratory research.

Any marketing of SARMs as supplements or performance enhancers violates laws in both the US and UK. The FDA and MHRA have issued multiple warnings emphasizing that point.
That’s why companies like Max Muscle Labs, which focus on analytical-grade materials and transparency, play a crucial role — by providing properly tested compounds and full Certificates of Analysis (COAs) for legitimate research.

MML:

That’s precisely our philosophy. We believe in separating scientific research from consumer misuse — making sure the data remains transparent and reliable.

Dr. Morris, as a closing thought: what excites you most about SARMs research moving forward?

Dr. Morris:

I’d say the potential for precision anabolism — the ability to stimulate growth and repair only where it’s needed.
If SARMs or their successors can help us better understand how to control tissue-specific signaling, it could influence not just muscle and bone research, but aging, neurobiology, and even regenerative medicine.

It’s less about “muscle enhancement” and more about decoding the body’s repair language — that’s where the real future lies.

🧠 MML Commentary

Dr. Morris’s insights highlight what makes SARMs fundamentally distinct from older compounds: selectivity, structure, and scientific intent.
While anabolic steroids and prohormones act broadly and unpredictably, SARMs represent a data-driven, research-focused approach to understanding androgen biology.

At Max Muscle Labs, we see it as our mission to support this ongoing scientific exploration — through transparency, verified purity, and a commitment to ethical research.

Follow Dr Morris on Linkedin

🧩 The Bottom Line

SARMs differ from steroids and prohormones in precision, selectivity, and intent.

• Steroids are powerful but non-selective; they enhance growth at a systemic cost.
• Prohormones act as steroid precursors, carrying the same risks with less control.
• SARMs, by contrast, are nonsteroidal, receptor-specific molecules created for controlled research — tools for understanding how androgens work at the cellular level.

Their emergence marks a shift from brute-force hormonal manipulation to targeted molecular modulation, mirroring the evolution of pharmacology itself.

⚠️ Research Disclaimer

SARMs are investigational compounds. They are not approved by the FDA, FSA, or MHRA for human or veterinary use. All information provided here is for educational and scientific purposes only.

📚 References

• Gao, W., et al. “Selective Androgen Receptor Modulators (SARMs): A Novel Approach to Androgen Therapy.” Endocrine Reviews, 2005.
• Dalton, J.T., & Taylor, R.P. “Selective Androgen Receptor Modulators: Concept and Development.” Endocrine Reviews, 2016.
• Kicman, A.T. “Pharmacology of anabolic steroids.” British Journal of Pharmacology, 2008.
• Basaria, S. “Androgen abuse in athletes: Detection and consequences.” JCEM, 2010.
• Narayanan, R. et al. “Androgen receptor signaling in target tissues.” Molecular and Cellular Endocrinology, 2018.