# Peptides vs. SARMs vs. Hormones vs. Supplements: The Difference

> A clinical explainer separating true peptides from the SARMs, small-molecule drugs, hormones, and supplements sold beside them on the same gray-market storefronts. Chemistry, evidence, FDA status, and anti-doping rules are all class-specific.

*Published 2026-07-01 · Updated 2026-07-01 · By The PeptideVox Editorial Desk*

The one-sentence answer
"Peptide" describes molecular structure — a short chain of amino acids. **SARMs, MK-677, 5-amino-1MQ, NAD+/NMN, tesofensine, and orforglipron are all non-peptide small molecules** sold in the same channel; **hormones** are a functional category (some are peptides, most popular ones are steroids); and **supplements** are a regulatory category (a few peptides qualify, injectable 'research peptides' do not). Conflating them is the single most common and most dangerous error in this market.[1](https://peptidevox.com/#r1)[4](https://peptidevox.com/#r4)

Walk any "peptide" storefront and you will find BPC-157 listed next to ostarine, MK-677, 5-amino-1MQ, NMN, and tesofensine — as if they were one family. They are not. A peptide is a short chain of amino acids joined by peptide bonds — typically 2 to about 50 residues, usually 500 to 5,000 daltons.[1](https://peptidevox.com/#r1) That is a chemistry definition. It is not a quality, legality, or evidence rating, and, crucially, most of the products sold alongside peptides on these sites are not peptides at all. They are different chemical classes that happen to share a gray-market storefront, "research chemical" labeling, and biohacking marketing.

*This article is informational and editorial content only. It is not medical advice, not a protocol to follow, and not a sourcing or buying guide. Many compounds discussed are not FDA-approved and are sold as "research chemicals not for human use." Consult a licensed clinician before any health decision.*

## What actually makes something a peptide?

A peptide is a short chain of amino acids joined by peptide bonds — covalent links between the carboxyl group of one amino acid and the amino group of the next.[1](https://peptidevox.com/#r1) Conventionally, chains of about 2 to 50 amino acids are "peptides"; longer chains that fold into stable three-dimensional structures are "proteins."[2](https://peptidevox.com/#r2) The body already runs on peptides: insulin, glucagon, oxytocin, and many hormones are peptides.[3](https://peptidevox.com/#r3) Therapeutically, peptides sit between small-molecule drugs like ibuprofen (~206 Da) and large biologics like antibodies (~150,000 Da) — binding targets with biologic-like specificity but smaller and often less immunogenic.[1](https://peptidevox.com/#r1) Their defining weakness is fragility: most are degraded by digestive enzymes and have short half-lives, which is why so many are injected rather than swallowed.[1](https://peptidevox.com/#r1) More than 80 peptide drugs are FDA-approved, with 150 to 200 more in development.[1](https://peptidevox.com/#r1)

The operational test is simple: **if a molecule's structure is a sequence of amino-acid residues, it is a peptide; if its structure is a steroid ring, a quinolinium salt, a dinucleotide, or any other non-amino-acid scaffold, it is not — no matter what website sells it.** You can confirm the scaffold of any compound yourself on a public chemistry database such as [PubChem](https://pubchem.ncbi.nlm.nih.gov/) rather than trusting the vendor's blurb.

## Why does this distinction actually matter?

This is not pedantry. Misclassifying these compounds has four concrete consequences. First, **evidence is class-specific and non-transferable.** "Peptides are FDA-approved and backed by RCTs" is true for semaglutide and false for BPC-157 — and entirely irrelevant to SARMs, which are a different drug class with their own record.[1](https://peptidevox.com/#r1) Second, **lab testing differs by chemistry.** A certificate of analysis for a peptide is a mass-spec/HPLC purity assay calibrated to an amino-acid sequence; a small molecule like MK-677 requires entirely different reference standards, so calling one a "peptide" on a COA is a red flag.[15](https://peptidevox.com/#r15) Third, **legal status is molecule-specific.** Some peptides are approved drugs; SARMs are categorically unapproved drugs the FDA warns about; orforglipron is now a fully approved drug.[4](https://peptidevox.com/#r4)[29](https://peptidevox.com/#r29) Fourth, **anti-doping rules are class-specific.** SARMs sit in WADA category S1, GH secretagogues like MK-677 in S2, and stimulants like tesofensine in S6 — an athlete who assumes "it's just a peptide" can test positive for a substance that was never a peptide.[14](https://peptidevox.com/#r14)

## How do peptides differ from SARMs?

This is the most consequential confusion in the market. Selective androgen receptor modulators are synthetic non-steroidal small molecules designed to bind the androgen receptor with tissue selectivity — aiming to build muscle and bone while sparing the prostate.[5](https://peptidevox.com/#r5) They are emphatically not amino-acid chains: ostarine (enobosarm/MK-2866), RAD-140, and LGD-4033 are all small organic molecules.[11](https://peptidevox.com/#r11) SARMs have been studied in real human trials — enobosarm completed a Phase 2 trial in advanced breast cancer[9](https://peptidevox.com/#r9) and is in Phase 2b development for preserving lean mass during GLP-1 therapy[10](https://peptidevox.com/#r10) — yet despite years of research, no SARM has ever been approved by the FDA or EMA, largely because of adverse effects.[5](https://peptidevox.com/#r5) A systematic review of 33 studies (n approximately 2,136) found elevated ALT, a liver-injury marker, in about 7% of exposed participants, with two cases of rhabdomyolysis.[5](https://peptidevox.com/#r5)

The safety profile is genuinely worse than most peptides. The FDA warns that SARMs can cause liver toxicity requiring hospitalization and may increase the risk of heart attack and stroke.[4](https://peptidevox.com/#r4) Published case reports tie LGD-4033 to hepatocellular liver injury in otherwise healthy users.[6](https://peptidevox.com/#r6)[7](https://peptidevox.com/#r7) Legally, SARMs "are considered unapproved drugs and cannot be legally marketed in the U.S. as a dietary supplement or drug," and the FDA continues active enforcement — for example a December 2025 warning letter to Atomix LLC for selling MK-2866 and RAD-140.[4](https://peptidevox.com/#r4)[8](https://peptidevox.com/#r8) A proposed SARMs Control Act to schedule them alongside anabolic steroids has been repeatedly introduced but not enacted.[12](https://peptidevox.com/#r12) WADA has prohibited SARMs as anabolic agents (S1) since 2008.[13](https://peptidevox.com/#r13)[14](https://peptidevox.com/#r14)

## How do peptides differ from hormones and supplements?

"Peptides vs. hormones" is a category error, not a true opposition. "Hormone" is a functional label — a signaling molecule acting on distant tissues — while "peptide" is a chemical label, and the two sets overlap. Some hormones are peptides: insulin (51 amino acids), glucagon, oxytocin, growth hormone, and GLP-1 are all peptide hormones.[3](https://peptidevox.com/#r3) But testosterone, estradiol, progesterone, and cortisol are steroid hormones — lipid molecules on a cholesterol-derived ring system, with no amino acids at all. When consumers say "hormones" in a TRT/HRT context, they almost always mean these steroids. The useful contrast is therefore peptide drugs versus steroid hormone therapy: different chemistry, receptors, regulatory pathways, and anti-doping rules (exogenous steroids are WADA S1).[14](https://peptidevox.com/#r14)

"Supplement" is likewise a regulatory category, not a chemical one. Dietary supplements are food-derived products that do not require premarket efficacy proof. A few peptides genuinely qualify: collagen peptides and creatine peptides are legal supplements.[3](https://peptidevox.com/#r3) But the injectable "research peptides" — BPC-157, TB-500, and the growth-hormone-releasing peptides — do not meet the statutory definition of a dietary ingredient, and several sit on the FDA's Category 2 bulk-substances list.[17](https://peptidevox.com/#r17) Calling an injectable peptide a "supplement" does not make it one, and the same logic exposes SARMs, MK-677, and 5-amino-1MQ sold "as supplements."[4](https://peptidevox.com/#r4)

## Which non-peptides get sold as peptides?

Six compounds are the highest-confusion items — routinely listed on "peptide" menus despite not one being a peptide. **MK-677 (ibutamoren)** is a non-peptide small molecule that mimics ghrelin; a 2-year RCT raised IGF-1 and lean mass but also increased insulin resistance, and it is Category 2 and WADA S2.[15](https://peptidevox.com/#r15)[16](https://peptidevox.com/#r16)[18](https://peptidevox.com/#r18) **5-Amino-1MQ** is a small-molecule NNMT-inhibitor quinolinium salt with animal-only evidence (Grade C).[19](https://peptidevox.com/#r19)[20](https://peptidevox.com/#r20)[21](https://peptidevox.com/#r21) **NAD+/NMN/NR** are nucleotide molecules that reliably raise blood NAD+ but show no proven muscle or functional anti-aging benefit in human trials.[22](https://peptidevox.com/#r22)[23](https://peptidevox.com/#r23)[24](https://peptidevox.com/#r24) **Tesofensine** is a small-molecule triple-monoamine reuptake inhibitor with real Phase 2 weight-loss data but no approval and WADA S6 status.[25](https://peptidevox.com/#r25)[26](https://peptidevox.com/#r26)[28](https://peptidevox.com/#r28) And **orforglipron** is the cleanest illustration: a non-peptide, small-molecule oral GLP-1 agonist, FDA-approved in April 2026 with Phase 3 weight loss of roughly 7.5% to 11.2% — proving a non-peptide can do a peptide's job.[29](https://peptidevox.com/#r29)[30](https://peptidevox.com/#r30)

  Regulatory and anti-doping status at a glance (US, 2026)

    CompoundChemical classFDA status (2026)WADA class

    Semaglutide / tirzepatidePeptideApproved drugsNot specifically prohibited
    BPC-157 / TB-500PeptidesUnapproved; Category 2 reviewProhibited (S0 context)
    SARMs (ostarine, RAD-140, LGD-4033)Non-steroidal small moleculeUnapproved; FDA-warnedProhibited (S1)
    MK-677 (ibutamoren)Non-peptide small moleculeUnapproved; Category 2Prohibited (S2)
    5-Amino-1MQNNMT-inhibitor small moleculeUnapprovedNot specifically listed
    NMN / NR / NAD+Nucleotide / dinucleotideSold as supplement (NMN contested)Generally permitted
    TesofensineSmall-molecule SNDRIInvestigational (orphan only)Prohibited (S6)
    OrforglipronNon-peptide small moleculeApproved (Apr 2026)Not specifically prohibited
    Testosterone / estradiolSteroid hormoneApproved prescription drugsProhibited (S1, exogenous)
    Collagen / creatine peptidesPeptidesLegal dietary supplementsPermitted

**Bottom line.** These are four different axes of definition — chemistry, target, function, and regulation — forced into one shopping cart. A compound can be a peptide and a hormone and, rarely, a supplement (a collagen peptide); a SARM is none of those. Name the chemistry precisely first: it is the single most important act of harm reduction in this market. Regulatory and anti-doping facts here are current as of June 2026 and are molecule-specific — re-verify each compound individually before relying on it.

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Source: https://peptidevox.com/the-science/peptides-vs-sarms-vs-hormones-vs-supplements
Index: https://peptidevox.com/llms.txt · Full text: https://peptidevox.com/llms-full.txt