Educational Wellness Information Only
This platform provides peer-reviewed research summaries and educational content about peptides for wellness and optimization purposes. Nothing on this site is intended as medical advice, diagnosis, or treatment. We do not claim any peptide can diagnose, treat, cure, or prevent any disease. Always consult a licensed healthcare provider before beginning any wellness protocol.
Statements on this site have not been evaluated by the FDA. Compounded preparations are subject to applicable state and federal regulations. Availability and eligibility vary.
Follistatin 344 vs MK-677 (Ibutamoren)
An educational, source-based comparison of Follistatin 344 and MK-677 (Ibutamoren) — how each peptide works, what it's researched for, and what to know before going deeper.
Myostatin-binding protein fragment researched for muscle growth.
A naturally occurring glycoprotein that binds and neutralizes myostatin and activin, releasing the natural brake on skeletal muscle growth in preclinical models.
- Muscular dystrophy models
- Skeletal muscle hypertrophy
- Age-related sarcopenia (preclinical)
- • Off-target effects on activin signaling (reproductive, cardiac) are a concern.
- • Not FDA-approved; banned by WADA.
Orally bioavailable non-peptide ghrelin mimetic.
Technically a small-molecule ghrelin receptor agonist (not a peptide), often grouped with peptide GH research. Orally bioavailable, it elevates GH and IGF-1 over 24 hours and increases appetite.
- GH/IGF-1 elevation in adults
- Lean mass and bone density in elderly
- Sleep quality (slow-wave sleep)
- • Not FDA-approved.
- • Insulin resistance and fluid retention reported.
- • Banned by WADA.
Trial-evidence rating
Educational grade reflecting how many peer-reviewed studies and FDA actions we cite for each peptide. Not a clinical recommendation.
Early-stage research; conclusions are tentative.
Early-stage research; conclusions are tentative.
Study-by-study comparison
| Peptide | Study | Source | Year | Summary |
|---|---|---|---|---|
| Follistatin 344 | Follistatin gene delivery enhances muscle growth and strength | Science Translational Medicine | 2009 | Demonstrated durable hypertrophy in primate models. |
| MK-677 (Ibutamoren) | MK-677 increases GH and IGF-1 in elderly adults | Annals of Internal Medicine | 2008 | Two-year RCT showing sustained IGF-1 elevation and lean mass increase. |
Side-effect & safety grid
- Off-target effects on activin signaling (reproductive, cardiac) are a concern.
- Not FDA-approved; banned by WADA.
- Not FDA-approved.
- Insulin resistance and fluid retention reported.
- Banned by WADA.
Educational summary of considerations reported in research literature — not a complete list of adverse events. Discuss with a licensed clinician before any use.
Follistatin 344 vs MK-677 (Ibutamoren) — Key differences
- Class: Follistatin 344 is classified as Muscle · Myostatin Inhibition, while MK-677 (Ibutamoren) is Growth Hormone Axis · Small Molecule.
- Primary research focus: Follistatin 344 — muscular dystrophy models; MK-677 (Ibutamoren) — gh/igf-1 elevation in adults.
- Tag: Muscle vs Growth hormone · Oral.