NR
About
About NR
Nicotinamide riboside (NR) is an NAD+ precursor and vitamin B3 analog commercially available as Tru Niagen and other supplements. It effectively raises blood NAD+ levels in humans with a well-established safety profile. Clinical trials demonstrate improved muscle function in older adults and metabolic benefits in specific populations. It is one of the most studied NAD+ precursors in human clinical research.
Science
Mechanism of Action
Phosphorylated to NMN and then to NAD+ by NRK enzymes in cells; raises NAD+ levels to support sirtuin-mediated gene expression regulation, PARP DNA repair activity, and mitochondrial energy production.
Dosing
Typical Protocol
250–500 mg oral once or twice daily; may be combined with pterostilbene for synergistic sirtuin activation.
⚠ Protocol information is for educational purposes only. Dosing must be determined by a licensed physician based on individual health status and goals.
Regulatory
Legal Status in 2026
This compound has completed clinical trials and received formal FDA approval for one or more indications. It can be legally prescribed by licensed physicians, filled at any licensed pharmacy, and may be covered by insurance. Off-label use by physicians is also legal. This is the highest level of regulatory clearance available in the US.
Evidence
Evidence Tier
Evidence from randomized controlled trials (RCTs) or large observational studies in humans. This is the gold standard — effects have been measured in controlled conditions and results are peer-reviewed and reproducible.
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