Head to head
Nicotinamide Riboside against NRH
The reduced form raises cellular NAD by 2.5 to 10 fold within an hour, more than NR or NMN at equivalent concentrations. It has never been given to a human being in a published trial and it is already sold to consumers, which is the comparison.
Column A
Nicotinamide RibosideNicotinamide Riboside (NR)
A well-studied NAD+ precursor that reliably raises NAD+ in humans. Raising the molecule is proven; the mouse lifespan programme that tested it found no effect.
Column B
NRHDihydronicotinamide riboside, the reduced form of nicotinamide riboside
Raises cellular NAD by 2.5 to 10-fold within an hour in cultured mammalian cells, more than NR or NMN at equivalent concentrations, and reaches tissues in mice. It has never been given to a human being in a published trial, and it is already sold to consumers.
Side by side, on the facts we can check
| Attribute | Nicotinamide Riboside | NRH |
|---|---|---|
| Category | Longevity | Longevity |
| FDA status | Sold as a supplement; not an approved drug | Not an approved drug and not an established dietary ingredient in the United States. It is sold by research-chemical and supplement vendors without any published human safety data. FDA has not evaluated it. |
| Half-life | Short | No human pharmacokinetic study has been published, so no half-life in people can be stated. The mouse work used intraperitoneal injection and oral gavage and reported tissue NAD rather than compound clearance. |
| Molecular weight | 255.2 Da | About 256 Da for the reduced free base, against 255 Da for the nicotinamide riboside cation. |
| Mechanism | Converts to NAD+ through the salvage pathway, restoring NAD+ that declines with age and supporting mitochondrial and repair enzymes. | NRH is converted to NMNH by an ATP-dependent kinase activity found in cell lysates that is independent of NRK1 and NRK2, and NMNH is then adenylylated by NMNAT enzymes to NADH, which enters the NAD pool. Bypassing the NRK step is the proposed reason NRH outperforms NR, since NRK1 expression is rate-limiting for NR utilisation and is not required here. Because the entry point is the reduced dinucleotide rather than the oxidised one, the reduced precursors also shift the NAD to NADH ratio differently from NR and NMN, which is the aspect of their pharmacology least understood and most relevant to whether they are safe. |
| Human studies cited | 4 | 1 |
| Legal status, US | Sold as a dietary supplement | Not approved; research use only |
Frequently asked questions
What is the difference between Nicotinamide Riboside and NRH?
Nicotinamide Riboside: A well-studied NAD+ precursor that reliably raises NAD+ in humans. Raising the molecule is proven; the mouse lifespan programme that tested it found no effect. NRH: Raises cellular NAD by 2.5 to 10-fold within an hour in cultured mammalian cells, more than NR or NMN at equivalent concentrations, and reaches tissues in mice. It has never been given to a human being in a published trial, and it is already sold to consumers.
Which has stronger research evidence, Nicotinamide Riboside or NRH?
This database does not grade compounds. It counts what was run in people: 4 of the 5 studies cited on the Nicotinamide Riboside profile were human work, against 1 of 4 for NRH. Those counts are of our own citation lists and understate any larger literature, and neither is a recommendation.
Are Nicotinamide Riboside and NRH FDA-approved?
Nicotinamide Riboside: Sold as a supplement; not an approved drug. NRH: Not an approved drug and not an established dietary ingredient in the United States. It is sold by research-chemical and supplement vendors without any published human safety data. FDA has not evaluated it..
Related posts
Blog articles that cover Nicotinamide Riboside or NRH, newest first.
Reviewed Sep 2026. This page sets two published records side by side. It is educational, it is not medical advice, and it contains no dosing protocols or recommendations for personal use.