Short answer: NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell, and it sits at the centre of energy metabolism, DNA repair and the sirtuin pathways that dominate ageing research. Cellular NAD+ levels fall with age in many tissues, which is why it has become one of the most searched longevity compounds in Canada. This guide covers what NAD+ is, why it declines, how it compares to NMN and NR, what the research has found, and how to buy research-grade NAD+ in Canada.
What is NAD+?
NAD+ is the oxidized form of nicotinamide adenine dinucleotide, a molecule made of two nucleotides joined through their phosphate groups. It exists in two states: NAD+, which accepts electrons, and NADH, which carries them. Shuttling between those two states is how cells move energy from food into the mitochondria to make ATP.
That alone would make it essential. But NAD+ also has a second job that is far more interesting to ageing researchers: it is a consumed substrate for several families of enzymes, including the sirtuins, the PARPs that repair DNA, and CD38. Those enzymes use NAD+ up, and the cell has to keep making more.
| Full name | Nicotinamide adenine dinucleotide (oxidized) |
|---|---|
| Molecular weight | ~663.4 Da |
| Class | Dinucleotide coenzyme (not a peptide) |
| Main roles studied | Redox metabolism, sirtuin activity, PARP-mediated DNA repair |
| TrueLabs vial sizes | 100 mg, 500 mg, 1000 mg |
| Reconstitution | Bacteriostatic water |
Is NAD+ a peptide?
No, and it is worth being clear about this because you will see “NAD+ peptide” all over the internet. Peptides are chains of amino acids. NAD+ is built from nucleotides: adenine, nicotinamide, two ribose sugars and two phosphates. It shows up in peptide shops because researchers studying mitochondrial and longevity pathways tend to buy it alongside peptides like SS-31 and MOTS-C, not because it is one.
Why NAD+ declines with age
Multiple studies in rodents and humans report that NAD+ levels fall with age in tissues such as muscle, liver, skin and brain. Researchers have proposed three main reasons, and the evidence suggests all three contribute:
- More consumption by CD38. CD38 is an enzyme that degrades NAD+, and its expression rises with age and inflammation. Work by Camacho-Pereira and colleagues in 2016 identified CD38 as a major driver of age-related NAD+ decline in mice.
- More DNA damage, more PARP activity. PARP enzymes use NAD+ to repair DNA. As damage accumulates, they consume more of the pool.
- Less recycling. Most NAD+ is rebuilt through a salvage pathway that depends on the enzyme NAMPT. Some studies report reduced NAMPT activity in aged tissue.
The result is a squeeze: more NAD+ being used, less being regenerated. That squeeze is the central hypothesis behind “NAD+ boosting” research.
NAD+ vs NMN vs NR
Most of the human NAD+ literature does not use NAD+ directly. It uses precursors, smaller molecules the cell converts into NAD+.
| NAD+ | NMN | NR | |
|---|---|---|---|
| What it is | The coenzyme itself | Nicotinamide mononucleotide, one step from NAD+ | Nicotinamide riboside, two steps from NAD+ |
| Molecular size | Largest (~663 Da) | ~334 Da | ~255 Da |
| Research use | Direct substrate in cell and enzyme assays | Precursor studies | Precursor studies |
For in vitro and enzyme work, NAD+ itself is often the most direct tool: you are supplying the molecule the enzyme actually uses, rather than relying on the cell’s own conversion machinery. That is the main reason labs studying sirtuins or PARPs buy NAD+ rather than a precursor.
What the research has studied
1. Sirtuins
Sirtuins are a family of seven enzymes (SIRT1 to SIRT7) that regulate gene expression, mitochondrial function and stress responses. Every one of them needs NAD+ to work. Verdin’s 2015 review in Science lays out why this link put NAD+ at the centre of metabolism and ageing research.
2. Mitochondrial function
Because NAD+ carries electrons into the mitochondrial respiratory chain, falling levels are associated with reduced mitochondrial efficiency in ageing models. Several rodent studies reported that restoring NAD+ with precursors improved markers of mitochondrial function in muscle and other tissues.
3. DNA repair
PARP1, the main DNA damage sensor, consumes NAD+ every time it signals a break. Researchers study NAD+ availability as a possible bottleneck in DNA repair capacity in aged cells.
4. Ageing models
Rajman, Chwalek and Sinclair’s 2018 review in Cell Metabolism summarized the in vivo evidence for NAD-boosting molecules across models of metabolic, cardiovascular, muscular and neurodegenerative ageing. A 2021 review by Covarrubias and colleagues in Nature Reviews Molecular Cell Biology updated the picture, covering both the promise and the open questions.
The honest caveat: the animal data is extensive. Human trials so far are mostly small, short and focused on whether precursors raise NAD+ levels, which they generally do. Whether that translates into meaningful outcomes in people is still an open question.
NAD+ alongside SS-31, MOTS-C and Epithalon
Researchers working on mitochondrial and longevity pathways often study NAD+ together with:
- SS-31: a tetrapeptide that targets cardiolipin on the inner mitochondrial membrane.
- MOTS-C: a peptide encoded in mitochondrial DNA, studied in metabolic regulation models.
- Epithalon: a tetrapeptide studied in telomerase and pineal research.
For an overview of every research category, see our guide to buying research peptides in Canada.
How to buy NAD+ in Canada
- Ships from inside Canada, so there is no customs hold and minimal time in transit.
- Batch-specific COA showing HPLC purity and identity confirmation for your lot.
- Clear mass per vial. NAD+ is sold in large quantities (hundreds of mg), so check the label matches the COA.
- Sealed, moisture-protected vials. NAD+ is hygroscopic and degrades faster once it absorbs water.
NAD+ price in Canada
| TrueLabs NAD+ | Price (pre-order) | Per mg |
|---|---|---|
| 100 mg | $26.00 | $0.26 |
| 500 mg | $65.00 | $0.13 |
| 1000 mg | $108.00 | $0.11 |
The 1000 mg vial is less than half the per-mg price of the 100 mg. Orders over $200 ship free anywhere in Canada.
Storage and handling
- Powder: keep sealed and dry, −20 °C long term, protected from light.
- In solution: NAD+ is noticeably less stable than in powder form, and degrades faster at alkaline pH and higher temperatures. Refrigerate at 2–8 °C and use promptly.
- Diluent: bacteriostatic water for multi-use lab vials.
Frequently asked questions
Cliquez sur une question pour afficher la réponse.
What is NAD+?
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme in every living cell, central to energy metabolism, DNA repair and sirtuin activity.
Is NAD+ a peptide?
No. NAD+ is a dinucleotide built from nucleotides, not amino acids. It is often sold by peptide suppliers because it is studied alongside mitochondrial peptides such as SS-31 and MOTS-C.
Why do NAD+ levels decline with age?
Research points to higher consumption by CD38 and PARP enzymes and reduced recycling through the NAMPT salvage pathway.
What is the difference between NAD+, NMN and NR?
NMN and NR are precursors the cell converts into NAD+. NAD+ is the coenzyme itself, which is why it is used directly in enzyme and cell assays.
How much does NAD+ cost in Canada?
At TrueLabs, from $26 for 100 mg to $108 for 1000 mg during the current pre-order, about $0.11 per mg in the largest size.
Related reading
- NAD+ injection side effects
- MOTS-C, SS-31 & NAD+: the mitochondrial toolkit
- How to choose a research peptide supplier in Canada
- GHK-Cu copper peptide in Canada
- Buy BPC-157 in Canada
Selected research references
- Verdin E. NAD+ in aging, metabolism, and neurodegeneration. Science. 2015;350(6265):1208–1213. PubMed
- Rajman L, Chwalek K, Sinclair DA. Therapeutic potential of NAD-boosting molecules: the in vivo evidence. Cell Metab. 2018;27(3):529–547. PubMed
- Covarrubias AJ, Perrone R, Grozio A, Verdin E. NAD+ metabolism and its roles in cellular processes during ageing. Nat Rev Mol Cell Biol. 2021;22(2):119–141. PubMed
- Camacho-Pereira J, et al. CD38 dictates age-related NAD decline and mitochondrial dysfunction through an SIRT3-dependent mechanism. Cell Metab. 2016. PMC
All TrueLabs products are sold for in vitro and laboratory research use only. They are not intended for human or veterinary use, and nothing in this article is medical advice or a recommendation to use any compound.