What it is & primary uses
A vitamin B3-related NAD+ precursor that reliably raises blood NAD metabolites but has not established broad anti-aging benefits.
Main benefits
- Raises blood NAD+ metabolites
- Clinical performance and metabolic benefits remain inconsistent
Studied protocols
Research doses are grouped by outcome. They describe study designs—not a personal prescription.
300–1,000 mg/day
- Study duration
- 2–8 weeks
- Interpretation
- Dose-dependent biomarker increases are reproducible. A biomarker response is not proof of clinical benefit.
1,000–2,000 mg/day
- Study duration
- 6–12 weeks
- Interpretation
- Controlled studies commonly show no improvement in insulin sensitivity or mitochondrial and muscle outcomes.
04Food sources & equivalents＋
Can food provide a studied amount?
NR can occur in the food supply at trace levels, but no ordinary food serving reproduces the concentrated amounts used in supplement trials.
Trace dietary precursors rather than a standardized 300–1,000 mg NR dose
- How this was estimated
- No calculation is defensible because routine food databases do not provide a stable NR value suitable for gram-to-serving conversion.
- Important limitation
- Niacin, tryptophan, nicotinamide and NR all participate differently in NAD metabolism; they are not interchangeable milligram for milligram.
Food equivalents compare ingredient mass using published composition values. They do not prove equal absorption, formulation, physiological effect, safety or personal need.
Source: NR dose, safety and NAD+ biomarker trial ↗05How to take it for absorption & tolerance＋
With or without food
Daily NR raises blood NAD metabolites across studied protocols; taking it with food has not been shown to create a clinical anti-aging effect.
- Practical approach
- Use a consistent schedule and take with food if it improves gastrointestinal tolerance.
- Watch for
- Do not combine multiple NAD-precursor products without totaling them; biomarker elevation is not the same as clinical benefit.
Meal guidance reflects human pharmacokinetic, clinical, official-label or evidence-review sources where available. A food pairing can change absorption or tolerability, but does not make a supplement necessary, effective or safe for every person.
Source: NR dose-response and safety trial ↗06Supplement interaction check＋
An unlisted pair means no established pair-specific interaction was identified in this review—not proof that every dose, product or person is safe.
This is not proof that every dose, product or user context is safe. Medication and condition checks still apply.
07Research notes＋
Limited: NR reliably raises blood NAD+ metabolites, but biomarker elevation has not translated consistently into better metabolic, muscle, cognitive or longevity outcomes.
A higher NAD+ blood marker is not itself proof of longer life, better cognition or improved mitochondrial function.
08Scientific references＋
Peer-reviewed human research and formal evidence reviews. Open each source to inspect the complete paper record.
Long-term NR safety and NAD+ metabolism
Dose context: 100, 300 or 1,000 mg/day for 8 weeks
Raised whole-blood NAD+ dose-dependently and was tolerated; the industry-funded study was designed around safety and biomarkers, not longevity.
NR in healthy middle-aged and older adults
Dose context: 500 mg twice daily for 6 weeks
Raised NAD+ metabolites; exploratory blood-pressure and arterial-stiffness signals required confirmation.
NR and skeletal-muscle mitochondria
Dose context: 1,000 mg twice daily for 12 weeks
Did not improve muscle NAD metabolites, mitochondrial respiration, content or morphology in obese insulin-resistant men.
09Expert & media references＋
Podcast and practitioner statements are clearly separated from research. They may explain practice or emerging ideas, but do not prove efficacy.