MK-677 vs MOTS-c
Well Studied vs Well Studied
synergistic Mechanism-based · 51% MK-677 helps counteract the insulin-disrupting effects of MOTS-c. A smart combination — the insulin sensitizer mitigates metabolic side effects.
Molecular Data
MK-677 MOTS-c
Weight 624.77 Da 2,174.6 Da
Half-life ~24 hours ~30 minutes
Chain — 16 amino acids
Type Non-peptide ghrelin receptor agonist Mitochondrial-derived peptide (MDP)
Key Benefits
MK-677
01 97% increase in 24-hour growth hormone secretion
02 40-72% elevation in IGF-1 levels
03 Enhanced sleep quality with improved REM patterns
04 Preferential lean tissue gains of 1.1-2.7kg over 8-12 months
05 15% basal metabolic rate increase within 2 weeks
06 Oral administration (no injections required)
MOTS-c
01 Enhanced insulin sensitivity (~30% improvement)
02 Improved glucose metabolism and tolerance
03 AMPK pathway activation
04 Mitochondrial function optimization
05 Exercise performance enhancement (12-15% improvement)
06 Potential lifespan extension (6.4% median increase in mice)
Dosing Protocols
MK-677
Start 12.5mg daily, increase to 25mg based on tolerance / Once daily, preferably at bedtime on empty stomach
MOTS-c
Start 5mg daily, increase to 10-15mg based on goals / Daily for metabolic support, or 3x weekly for anti-aging
Metabolic health 5-10mg Once daily
Anti-aging protocol 15mg 3x weekly
Exercise performance 10-15mg Pre-workout
Conservative start 5mg Once daily
Side Effects
MK-677
Appetite stimulation (>50% of users)
Water retention (30-40%)
Lethargy (20-30%)
Fasting glucose elevation (5-15mg/dL)
Note on testosterone suppression: at doses up to 20 mg daily, MK-677 is unlikely to cause significant testosterone suppression on its own. Above 20 mg daily, the likelihood of suppression and other side effects (insulin resistance, water retention, lethargy) increases. The case report documenting 85.7% testosterone suppression involved co-administration with LGD-4033, a SARM known to be profoundly suppressive, making the SARM the likely primary driver of that suppression.
MOTS-c
Generally well-tolerated in animal studies with minimal side effects
Mild injection site reactions (redness, swelling)
Contraindications
Heart disease or congestive heart failure
Diabetes or pre-diabetes
Active cancer
Severe cardiovascular disease
Pregnancy or breastfeeding
Pregnancy or breastfeeding
WADA prohibited substance (banned for athletic competition)
Limited long-term human safety data
Research Evidence
MK-677 MOTS-c
Status Well Studied Well Studied
References 7 studies 5 studies
Latest July 2024 August 2025
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.