NAD+, NMN and NR compared
Three molecules, one pathway
NAD+, NMN and NR are routinely treated as interchangeable in search results and marketing. They are three distinct chemicals that sit next to each other on the same salvage pathway, and the distinction decides what a certificate of analysis is actually confirming.
| Molecule | Full name | Molecular weight | Structure |
|---|---|---|---|
| NR | Nicotinamide riboside | About 255 Da (free), 291 Da as chloride | Nicotinamide joined to ribose |
| NMN | Nicotinamide mononucleotide | About 334 Da | NR plus one phosphate |
| NAD+ | Nicotinamide adenine dinucleotide | About 663 Da | NMN joined to AMP |
Each step adds a piece. NR is the smallest; adding a phosphate gives NMN; joining NMN to adenosine monophosphate gives NAD+. NAD+ is the molecule that enzymes use as a coenzyme. NR and NMN are precursors.
How cells convert them
Cells make NAD+ by several routes. The salvage pathway is the one all three molecules sit on.
- Nicotinamide is converted to NMN by the enzyme NAMPT, which is the rate-limiting step.
- NR is converted to NMN by the kinases NRK1 and NRK2.
- NMN is converted to NAD+ by the NMNAT enzymes.
Whether added NMN or NAD+ enters cells intact, or is broken down outside the cell and rebuilt inside, has been argued in the literature for a decade. Transporters for NMN have been proposed and disputed. The cell-culture and rodent studies that make up most of the evidence answer the question differently depending on the model. None of that is settled, and a research material cannot settle it.
Product status is a separate question
Food ingredients, finished medicines and laboratory reagents have different product contexts. An authorisation for one formulation does not establish the status of another. This article compares chemical identities, rather than determining the regulatory status of a particular supply arrangement.
What a research NAD+ reagent is
Research NAD+ is nicotinamide adenine dinucleotide, the oxidised dinucleotide, normally supplied as lyophilised powder. It is not NMN and it is not NR. A batch certificate confirms that by mass, and reports purity by HPLC, which for NAD+ is normally run with UV detection at 260 nm.
NAD+ is hygroscopic and sensitive to light, and in solution it breaks down to nicotinamide and ADP-ribose, faster at alkaline pH. A purity figure measured on the solid therefore describes the solid on the date of the test. The earlier page on NAD+ in cellular energy research covers the coenzyme's biochemical roles.
EPS documentation
Use the research catalogue to check the exact name, labelled amount and format. The COA library publishes the original Janoshik reports selected for EPS, retaining the original report client name and any missing batch fields. Literature findings and another supplier's analytical results are not evidence about an EPS batch.