Longevity & Aging · Supplements
NAD+ precursors (NMN, NR) increases cellular NAD+
In plain terms: Do NMN or NR supplements raise NAD+, a key cell-fuel molecule?
Strong support Longevity & Aging 💰 Industry COI noted🔬 Includes disconfirming
Part of: 🧪 nad+ precursors (nmn, nr)
RefutedContestedStrong support
consensus score 0.78
Yes — they reliably raise blood levels in trials, but that is not a proven health benefit.
📅 Last reviewed: 2026-07-14 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
13 support 0 contradict 1 tested null 3 mixed · 17 sources, 12 independent groups · 2 superseded — pooled inside a review, counted once
What the evidence shows
NMN/NR supplementation reliably raises blood NAD+ in human RCTs - the best-supported NAD claim (multiple independent groups + meta-analysis).
The evidence (19)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Ahmadi A, Begue G, Valencia AP, Norman JE, Lidgard B, Bennett BJ, Van Doren MP, Marcinek DJ, Fan S, Prince DK, Gamboa J, Himmelfarb J, de Boer IH, Kestenbaum BR, Roshanravan B 2023 · JCI Insight | RCT | mixed | low | Crossover RCT in CKD: NR (1000 mg/d) altered NAD-dependent TCA/metabolome but did not improve VO2/work; NAD-pathway engagement without functional gain. |
| Yi L, Maier AB, Tao R, Lin Z, Vaidya A, Pendse S, Thasma S, Andhalkar N, Avhad G, Kumbhar V 2023 · GeroScience | RCT | supports | moderate | FT RCT n=80 dose-resp blood NAD up p<0.001; CAVEAT industry co-sponsored, colorimetric assay |
| Conze D, Brenner C, Kruger CL 2019 · Scientific Reports | RCT | supports | high | 8-wk RCT in overweight adults: NR (NIAGEN) dose-dependently increased whole-blood NAD+ ~22-51% vs placebo; well tolerated. |
| Remie CME, Roumans KHM, Moonen MPB, Connell NJ, Havekes B, Mevenkamp J, Lindeboom L, de Wit VHW, van de Weijer T, Aarts SABM, Lutgens E, Schomakers BV, Elfrink HL, Zapata-Pérez R, Houtkooper RH, Auwerx J, Hoeks J, Schrauwen-Hinderling VB, Phielix E, Schrauwen P 2020 · Am J Clin Nutr | RCT | mixed | moderate | 6-wk NR in obese humans raised muscle NAD+ metabolites (MeNam) and altered body composition, but several metabolic endpoints null. |
| Berven H 2026 · (2026 phase-I PK trial) | RCT | supports | moderate | Phase-I PK RCT (n=12: 6 healthy + 6 Parkinson) 1200 mg/day oral NR or NMN: blood NAD+ increased, plateauing ~2 weeks; cerebral NAD+ measurably rose by 4 weeks — direct human evidence the precursors raise NAD+ (large interindividual variation). |
| Trammell SA, Schmidt MS, Weidemann BJ, Redpath P, Jaksch F, Dellinger RW, Li Z, Abel ED, Migaud ME, Brenner C 2016 · Nature Communications | RCT | supports | high | First-in-human: single oral NR dose dose-dependently raised blood NAD+ metabolome up to ~2.7x; landmark oral bioavailability proof. |
| Pencina KM, Lavu S, Dos Santos M, Beleva YM, Cheng M, Livingston D, Bhasin S 2023 · J Gerontol A | RCT | supports | moderate | MIB-626 microcrystalline NMN significantly increased circulating NAD and its metabolome ↩ SUPERSEDED — pooled in the review above, counted once |
| Prokopidis K, Moriarty F, Bahat G, McLean J, Church DD, Patel HP 2025 · J Cachexia Sarcopenia Muscle | meta-analysis | tested-null | moderate | SR/MA of NMN & NR RCTs: precursors raise NAD+ but no consistent benefit on muscle mass/function; honest "raises NAD+, downstream effects unproven. |
| Brakedal B, Dölle C, Riemer F, Ma Y, Nido GS, Skeie GO, Craven AR, Schwarzlmüller T, Brekke N, Diab J, Sverkeli L, Skjeie V, Varhaug K, Tysnes OB, Peng S, Haugarvoll K, Ziegler M, Grüner R, Eidelberg D, Tzoulis C 2022 · Cell Metabolism | RCT | supports | high | NADPARK: 30-day NR significantly augmented cerebral and blood NAD+ in Parkinson's patients (variable responders); independent group, brain NAD+. |
| Kuerec AH, Wang W, Yi L, Tao R, Lin Z, Vaidya A, Pendse S, Thasma S, Andhalkar N, Avhad G, Kumbhar V, Maier AB 2024 · Mech Ageing Dev | RCT | supports | moderate | Post-hoc of NMN RCT: dose-dependent rise in blood NAD+ across 300-900 mg/d in healthy adults; confirms NMN raises blood NAD+. |
| Berven H, Kverneng S, Sheard E, Søgnen M, Af Geijerstam SA, Haugarvoll K, Skeie GO, Dölle C, Tzoulis C 2023 · Nat Commun | RCT | supports | high | NR-SAFE: high-dose NR (3000 mg/d) safely raised whole-blood NAD+ up to ~5-fold in Parkinson's; dose-response confirmation. |
| Martens CR, Denman BA, Mazzo MR, Armstrong ML, Reisdorph N, McQueen MB, Chonchol M, Seals DR 2018 · Nat Commun | RCT | supports | moderate | FT crossover n=24 NAD+ +60% but p=0.048 one-sided unadj; NAAD more robust; NIAGEN/ChromaDex. Holds |
| Elhassan YS, Kluckova K, Fletcher RS, Schmidt MS, Garten A, Doig CL, Cartwright DM, Oakey L, Burley CV, Jenkinson N, Wilson M, Lucas SJE, Akerman I, Seabright A, Lai YC, Tennant DA, Nightingale P, Wallis GA, Manolopoulos KN, Brenner C, Philp A, Lavery GG 2019 · Cell Rep | RCT | supports | high | 21-day NR in aged men raised skeletal-muscle and blood NAD+ metabolome and lowered inflammatory cytokines; tissue-level NAD+ augmentation. |
| Shoji M, Kato H, Koshizaka M, Kaneko H, Baba Y, Ishikawa T, Teramoto N, Kinoshita D, Yamaguchi A, Maeda Y, Inaba Y, Shiko Y, Ozawa Y, Bohr VA, Maezawa Y, Yokote K 2025 · Aging Cell | RCT | supports | moderate | Crossover RCT: NR raised NAD+ and gave benefits in Werner-syndrome patients; independent confirmation of NR->NAD+ in a clinical population. |
| Dollerup OL, Christensen B, Svart M, Schmidt MS, Sulek K, Ringgaard S, Stødkilde-Jørgensen H, Møller N, Brenner C, Treebak JT, Jessen N 2018 · Am J Clin Nutrition | RCT | mixed | moderate | 12-wk NR RCT in obese men: NAD-metabolome shifts but blood NAD+ rise not statistically significant; no insulin-sensitivity benefit (raises-NAD signal weaker here). |
| Christen S, Redeuil K, Goulet L, Giner MP, Breton I, Rota R, Frézal A, Nazari A, Van den Abbeele P, Godin JP, Nutten S, Cuenoud B 2026 · Nat Metab | RCT | supports | moderate | Head-to-head: three NAD precursors differentially raise the NAD+ metabolome in humans; NMN/NR raise NAD+ but compartment/route effects differ. |
| Chen F, Zhou D, Kong AP, Yim NT, Dai S, Chen YN, Hui LL 2024 · Current Diabetes Reports | meta-analysis | supports | moderate | SR/MA of NMN RCTs: significant elevation of blood NAD+ with NMN, but no robust glucose/lipid benefit; corroborates the NAD+-raising endpoint specifically. |
| Zhang J, Poon ET, Wong SH 2025 · Crit Rev Food Sci Nutr | meta-analysis | supports | moderate | MA (12 RCTs, n=513): NMN significantly elevates blood NAD, but most clinical metabolic outcomes not improved |
| Yoshino M, Yoshino J, Kayser BD, Patti GJ, Franczyk MP, Mills KF, Sindelar M, Pietka T, Patterson BW, Imai SI, Klein S 2021 · Science | RCT | supports | high | Same RCT (NMN 250 mg/d, n=13 vs placebo n=12, 10 wk): basal PBMC NAD+ 'increased after 10 weeks of NMN treatment, but did not change after placebo'; 240-min PBMC NAD+ AUC 43% greater in NMN group (p<0.01). Muscle NAD+ itself did NOT change in either group; only NAD+ metabolites (N-methyl-nicotinamide, 2PY, 4PY) rose, read by the authors as increased turnover. Blood-cell NAD+ rise supports; tissue NAD+ not raised. ↩ SUPERSEDED — pooled in the review above, counted once |
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