Nicotinamide Riboside

The better-studied NAD+ precursor — reliably raises NAD+, still short on hard human outcomes.

Overall grade: Grade C
Last revised: Jul 10, 2026; 2
graded outcomes: 0
references listed

A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.

1 at grade A · 1 at grade C — 2 graded rows

What is known

Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.

Outcome	Grade	Effect size	Agreement
Blood NAD+Reliably raised	Evidence grade A	Moderate	high
Physical / metabolic functionInconsistent	Evidence grade C	Small	mixed

Blood NAD+Evidence grade A
Reliably raised
Moderatehigh
Physical / metabolic functionEvidence grade C
Inconsistent
Smallmixed

What is uncertain

Read off the same rows as above. Nothing here is added that the entry does not itself record.

Thin evidence: Physical / metabolic function (grade C).

The evidence in words

What it is

Nicotinamide riboside is a vitamin-B3-related NAD+ precursor, the most clinically-studied of the NAD boosters.

How it works

It is converted to NAD+, aiming to restore the age-related decline in this central coenzyme.

What the evidence shows

Human trials consistently show NR raises NAD+ and is safe, but functional and metabolic benefits have been small and inconsistent, and longevity effects are unproven. Ahead of NMN on safety data, level with it on unproven benefit.

How to use it

300–1,000 mg/day.

Safety & interactions

Well tolerated in trials to a year.

Bottom line

The most-vetted NAD+ booster for safety, but the clinical payoff still hasn't shown up. Fine to trial, don't expect miracles.

How it is used

As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.

Standard: 300–1,000 mg/day.

Entries that share this one's tags or conditions.

NMNAn NAD+ precursor with real biomarker effects (NAD+ rises) and no proven clinical or longevity outcomes yet.Evidence grade C
Nicotinamide Riboside for Blood NAD+Evidence grade A — Reliably raisedEvidence grade A
Nicotinamide Riboside for Physical / metabolic functionEvidence grade C — InconsistentEvidence grade C
Nicotinamide Riboside: dosage and how to take it300–1,000 mg/day.Evidence grade C

Sources

This entry lists no references of its own.

Last revised Jul 10, 2026. A grade is this entry's reading of the evidence, not medical advice.