HGH Fragment 176-191
Modified fragment of human growth hormone (amino acids 176-191) that stimulates lipolysis without anabolic or diabetogenic effects.
🔬 Mechanism of Action
HGH Fragment 176-191 is a truncated analog of human growth hormone consisting of amino acids 176-191 from the C-terminal region. This specific fragment contains the fat-burning activity of HGH without the growth-promoting, diabetogenic, or IGF-1-raising effects.
The fragment stimulates lipolysis (fat breakdown) by mimicking the way natural growth hormone regulates fat metabolism. It also inhibits lipogenesis (fat formation). Unlike HGH, it does not compete with human growth hormone receptors and does not induce insulin resistance.
Source: PMID: 11713213
📜Background & History
HGH Fragment 176-191 is the C-terminal fragment of human growth hormone. Originally identified by researchers studying which region of hGH drives lipolysis, Frank and colleagues showed the 176-191 region contains the lipolytic activity while the 1-43 region drives the diabetogenic IGF-1 effects. This makes Fragment 176-191 a selective fat-burning peptide without GH's anabolic or glucose-altering effects. Related to AOD-9604 (which adds a tyrosine for stability), it remains a popular research peptide for body composition.
🎯 Research Use Cases
- ✓Selective lipolysis without blood glucose effects
- ✓Body recomposition: fat reduction preserving muscle
- ✓Obese or insulin-resistant individuals seeking GH-like fat loss
💉 Dosing Protocol
| Typical Dose | 250-500 mcg/day |
| Frequency | 1-2× daily (fasted) |
| Half-Life | ~30 minutes |
| Common Vial Sizes | 2 mg, 5 mg |
🧪 Reconstitution Example
⚠️Safety & Considerations
Research peptide. Does not affect blood glucose or IGF-1 levels. No significant side effects reported. Must be administered in a fasted state for optimal fat mobilization.
⚡Interactions & Contraindications
Does not elevate IGF-1 or affect glucose — advantageous in metabolic patients. Minimal documented drug interactions. Lower potency for fat loss than full GH — dose accordingly.
🔗Synergies & Common Stacks
Fragment handles fat burning; CJC-1295 drives GH's anabolic and recovery benefits. Splits GH's two main effects for targeted outcomes.
Same rationale — Ipamorelin provides clean GH elevation for recovery; Fragment 176-191 handles the fat loss component without glycemic impact.
❓ Frequently Asked Questions
Is HGH Fragment 176-191 the same as AOD-9604?▼
Must I inject Frag 176-191 fasted?▼
📖 References
- Ng FM, et al. “Fat metabolism and growth hormone: investigation with GH fragment 176-191.” Obes Rev (2000). PMID: 12119988