What Is NAD+?
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell. It plays a critical role in energy metabolism, DNA repair, and cellular signaling. While technically not a peptide (it's a dinucleotide), NAD+ is widely sold alongside peptides due to overlapping customer interest in longevity and optimization.
NAD+ levels naturally decline with age. This decline has been linked to many hallmarks of aging, driving massive consumer interest in supplementation through oral precursors, injections, and IV infusions.
Quick Facts
| Property | Detail |
|---|---|
| Type | Coenzyme (dinucleotide, not a peptide) |
| Found In | Every living cell |
| Key Role | Energy metabolism, DNA repair, sirtuin activation |
| Age-Related Decline | Yes — levels drop significantly with age |
| OTC Available | Yes (as NMN or NR precursors) |
| Prescription Forms | IV infusion, subcutaneous injection, nasal spray |
Research Areas of Interest
- Cellular energy production — essential cofactor in mitochondrial function
- DNA repair — required by PARP enzymes that fix DNA damage
- Sirtuin activation — NAD+ fuels sirtuins, proteins linked to aging and metabolic regulation
- Age-related decline — declining NAD+ levels correlate with aging biomarkers
- Neuroprotection — studied for potential benefits in neurodegenerative conditions
NAD+ Precursors Explained
You don't have to take NAD+ directly — several precursors convert to NAD+ in the body:
| Precursor | Full Name | OTC Available | Typical Cost | Notes |
|---|---|---|---|---|
| NMN | Nicotinamide Mononucleotide | Yes | $30-80/month | Most popular oral precursor |
| NR | Nicotinamide Riboside | Yes (Tru Niagen) | $40-60/month | Patented, well-studied |
| Niacin | Vitamin B3 | Yes | $5-15/month | Cheapest option; can cause flushing |
| Niacinamide | Nicotinamide | Yes | $5-15/month | No flushing; less direct pathway |
Delivery Routes Compared
| Route | Bioavailability | Convenience | Cost | Prescription? |
|---|---|---|---|---|
| IV Infusion | Highest (100%) | Low — clinic visit, 2-4 hours | $250-1,000/session | Yes |
| Subcutaneous Injection | High | Moderate — self-administered at home | $150-400/month | Yes |
| Nasal Spray | Moderate | High — quick, non-invasive | $100-250/month | Yes |
| Oral NMN/NR | Lower (debated) | Highest — daily capsule | $30-80/month | No |
What to Look For When Buying
Oral Supplements (NMN/NR)
- Third-party testing — look for NSF, USP, or independent lab certification
- Purity verification — the NMN market has had contamination issues
- Proper storage — NMN degrades at high temperatures
- Brand reputation — choose brands with published testing results
Injectable/IV NAD+
- Must be sourced from a licensed compounding pharmacy
- Sterility testing — IV/injectable products must meet USP 797 standards
- Concentration and pH should be clearly specified
- Endotoxin testing results required
Never use research-grade NAD+ for injection. IV and subcutaneous NAD+ must come from a licensed compounding pharmacy that meets USP sterile compounding standards.
Storage Guide
| Form | Temperature | Key Concern |
|---|---|---|
| Oral supplements (NMN/NR) | Cool, dry place; refrigeration recommended | Heat degrades NMN rapidly |
| Injectable/IV | 2-8°C (refrigerate) | Protect from light |
| Research powder | 2-8°C | Moisture-sensitive |
NAD+ degrades faster than most peptides — always check expiration dates and store properly.
Key Sourcing Tips
- For general longevity interest, start with oral NMN or NR from a reputable supplement brand with third-party testing
- For injectable NAD+, only use a licensed compounding pharmacy — never research-grade products
- Be skeptical of extreme anti-aging claims — NAD+ research is promising but still evolving
- IV NAD+ clinics vary widely in quality — verify the clinic sources from a licensed 503A/503B pharmacy
- Store all NAD+ products properly — degradation is a real and common issue