What is NAD+?

NAD+ is nicotinamide adenine dinucleotide. As the name says, it is a dinucleotide: two nucleotides joined through their phosphate groups, one carrying adenine and the other nicotinamide. There is no chain of amino acids in it, which is why it is not a peptide. Its main job is to carry electrons. When your cells break down glucose and fat, NAD+ accepts the electrons released and becomes NADH, which hands them on inside the mitochondria to drive the production of ATP, the cell's energy currency. The same coenzyme is also consumed by enzyme families that do not use it for energy at all: the sirtuins, CD38 and the poly(ADP-ribose) polymerases that repair DNA. Through them it reaches into metabolic pathways, DNA repair, chromatin remodelling, cellular senescence and immune-cell function, and tissue NAD+ levels are reported to decline gradually with age in rodents and in humans Covarrubias AJ et al. NAD+ metabolism and its roles in cellular processes during ageing. Nat Rev Mol Cell Biol 2021. PMID 33353981. The same review is explicit that how to restore NAD+ safely, and whether doing so benefits ageing humans, remains to be learnt. Four terms get confused with one another, so here is each in one line.

NAD+ is the oxidised form of the coenzyme, the state that is ready to accept electrons, and the reference molecule for everything below. It is not a peptide.

NADH is the same molecule after it has picked up electrons and a hydrogen. NAD+ and NADH are two states of one coenzyme, converting back and forth constantly; a cell holds both at once. It is not a peptide either.

NAD+ precursors are the smaller molecules your cells build NAD+ from: nicotinamide riboside (NR), nicotinamide mononucleotide (NMN) and the niacin vitamins, nicotinic acid and nicotinamide. They are inputs to NAD+ synthesis, not NAD+ itself, and they are what nearly all the human trials have studied; we set the coenzyme against two of them at NAD+ vs NMN and NAD+ vs nicotinamide riboside.

Peptides are short chains of amino acids joined by peptide bonds, and they act by binding a receptor and passing on a signal, which NAD+ never does. The phrase "NAD+ peptide" exists only because NAD+ is sold alongside peptides, including here. MOTS-c, the other molecule we list under mitochondrial peptides, is a genuine peptide, and the pairing shows the difference: one is a signal, the other is machinery.

What the human evidence shows depends on which molecule was given. For the oral precursors, the trials agree on one point: they raise blood NAD+. The first pharmacokinetic trial of nicotinamide riboside in people found that single doses produced dose-dependent rises in the blood NAD+ metabolome Trammell SA et al. Nicotinamide riboside is uniquely and orally bioavailable in mice and humans. Nat Commun 2016. PMID 27721479, and an eight-week randomised, double-blind, placebo-controlled trial in overweight but otherwise healthy adults recorded whole-blood NAD+ rises of 22%, 51% and 142% across its three strengths within two weeks, sustained to the end, with no flushing and no difference in adverse events from placebo Conze D et al. Safety and Metabolism of Long-term Administration of NIAGEN (Nicotinamide Riboside Chloride) in a Randomized, Double-Blind, Placebo-controlled Clinical Trial of Healthy Overweight Adults. Sci Rep 2019. PMID 31278280. Whether a higher level changes anything downstream is less clear. A meta-analysis of eight randomised trials of NMN in 342 mostly non-diabetic adults found no significant benefit on fasting glucose, fasting insulin, glycated haemoglobin, insulin resistance or lipids Chen F et al. Effects of Nicotinamide Mononucleotide on Glucose and Lipid Metabolism in Adults: A Systematic Review and Meta-analysis of Randomised Controlled Trials. Curr Diab Rep 2024. PMID 39531138, while a 60-day placebo-controlled trial of NMN in 80 healthy middle-aged adults reported a larger gain in six-minute walking distance than placebo and no difference in insulin resistance Yi L et al. The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial. Geroscience 2023. PMID 36482258. For NAD+ given directly, the record is thinner. A pilot study that infused NAD+ intravenously for six hours found no change in plasma NAD+ or its metabolites for the first two hours, consistent with the coenzyme being cleared from the blood and broken down as fast as it arrived, and it was the first report of what happens to infused NAD+ in people at all Grant R et al. A Pilot Study Investigating Changes in the Human Plasma and Urine NAD+ Metabolome During a 6 Hour Intravenous Infusion of NAD+. Front Aging Neurosci 2019. PMID 31572171. That is a pharmacokinetic study, not an outcome trial; the outcome trials above belong to NR and NMN taken by mouth, not to the coenzyme itself.

What we supply is NAD+ 1000: 1000 mg of NAD+ already in solution in a 3 ml pre-loaded multi-dose pen. Every batch is tested by an independent lab for identity by mass spectrometry, purity by HPLC and sterility. The certificate for your batch shows the HPLC purity figure and the concentration of the cartridge (mg/ml and total mg per 3 ml); reach it by scanning the QR code on the pen or from the certificate index. One statement covers regulatory status: no injectable NAD+ product holds a marketing authorisation as a medicine in the European Union. The oral precursors in the trials above are sold as food supplements, a different legal category from either a medicine or an injectable, and their results describe NR and NMN by mouth, not the coenzyme in this pen.