What Is NAD+? (And Is It a Peptide?)
A common search is "is NAD+ a peptide?" — and the short answer is no. Nicotinamide adenine dinucleotide (NAD+) is a pyridine nucleotide coenzyme, not a chain of amino acids. It is grouped with peptides commercially because researchers in the same fields work with both, but chemically it is a different class of molecule entirely.
Research use only. NAD+ is supplied strictly for in-vitro laboratory research. This page does not describe dosing, administration, or use in humans or animals, and makes no therapeutic claims.
What NAD+ is
NAD+ is an endogenous coenzyme and signalling molecule central to cellular metabolism. In its oxidised form it participates in the electron-transfer reactions that underpin oxidative phosphorylation, glycolysis and mitochondrial energy production. It exists in a balance with its reduced form (NADH), and the NAD+/NADH ratio is a key variable in metabolic research.
What researchers study
In biochemical and cellular systems, NAD+ is studied for its role in redox balance and as a substrate for NAD+-dependent enzymes, including:
- Sirtuins — implicated in chromatin regulation
- Poly(ADP-ribose) polymerases (PARPs) — implicated in DNA repair
- Cyclic ADP-ribose-generating enzymes — implicated in calcium signalling
Experimental outcomes depend heavily on intracellular NAD+/NADH ratios, compartmentalisation and the metabolic state of the model, so NAD+ is widely used as a reference compound in enzymology and metabolic research.
NAD+ precursors: NR and NMN
NAD+ itself is a large, charged molecule that crosses cell membranes poorly, so most applied research uses precursors that cells convert into NAD+ — chiefly nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). Both are nicotinamide (vitamin B3) derivatives and, like NAD+, neither is a peptide.
Precursor research is active but early, and results so far are mixed. In a 12-week trial of 80 adults aged 65 and over, a University of Copenhagen group compared NR against intermittent fasting and exercise, measuring biological age via DNA methylation and an AI analysis of 29 blood markers. The researchers reported that NR had little measurable effect on the biological-age measures — though it did reduce markers of inflammation — while fasting and exercise scored higher. The group has stated that this trial is not yet peer-reviewed or published, so the findings should be treated as preliminary rather than established.
A separately published clinical trial from the same group reported that NR reduced inflammation in people with chronic obstructive pulmonary disease (COPD).
How it is supplied
The NAD+ Kit is supplied with a Certificate of Analysis for laboratory use. As with all our products it is for in-vitro research only.
Related reading
- New to the topic? Start with what are research peptides?