Compare Peptides

Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.

Popular comparisons

NAD+

Nicotinamide Adenine Dinucleotide, NAD

Unregulated
Metabolic & Longevity

SS-31

Elamipretide, MTP-131

Investigational
Mitochondrial & Cardioprotective
Overview

A coenzyme found in all living cells that plays a central role in energy metabolism and cellular repair. NAD+ levels decline significantly with age. Injectable NAD+ and its precursors (NMN, NR) have become widely used in longevity and anti-aging protocols.

A synthetic tetrapeptide that targets the inner mitochondrial membrane, specifically binding to cardiolipin — a phospholipid critical for mitochondrial function. Developed by Stealth BioTherapeutics, SS-31 has been studied for heart failure, kidney disease, and age-related mitochondrial dysfunction.

Mechanism of Action

Serves as an electron carrier in cellular respiration (ATP production). Activates sirtuins (SIRT1-7), a family of proteins involved in DNA repair, inflammation regulation, and metabolic homeostasis. Also activates PARP enzymes involved in DNA damage repair.

Concentrates in the inner mitochondrial membrane where it binds cardiolipin, stabilizing the electron transport chain and reducing reactive oxygen species (ROS) production. Improves mitochondrial efficiency without affecting membrane potential. Reduces ischemia-reperfusion injury by protecting mitochondrial structure during oxidative stress.

Common Uses
  • Anti-aging and longevity protocols
  • Energy and cognitive enhancement
  • Addiction recovery support
  • Athletic performance and recovery
  • Metabolic health optimization
  • Mitochondrial dysfunction support
  • Cardiac protection
  • Kidney protection (renal ischemia)
  • Age-related energy decline
  • Exercise performance and recovery
Known Risks
  • IV infusions can cause flushing, nausea, chest tightness (usually transient)
  • Oral precursors (NMN, NR) generally well-tolerated
  • Long-term effects of supraphysiological dosing unknown
  • Theoretical concern: NAD+ may support cancer cell metabolism
  • Quality varies significantly across suppliers
  • Limited human clinical data outside of specific disease trials
  • Injection site reactions
  • Phase 3 trial for heart failure (PROGRESS-HF) did not meet primary endpoint
  • Long-term safety profile not established for general use
Regulatory Status
Unregulated

NAD+ itself is not FDA-approved as a drug. Injectable NAD+ is available through compounding pharmacies with a prescription. Oral precursors (NMN, NR) are sold as dietary supplements. Not on any FDA compounding category list — exists in a separate regulatory framework from the peptides affected by the 2026 reclassification.

Investigational

Currently in clinical trials for heart failure with preserved ejection fraction (HFpEF) and other mitochondrial diseases. Phase 3 PROGRESS-HF trial results were mixed. Not FDA-approved. Available as a research chemical. Not affected by the 2026 compounding regulatory changes.

This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.