Longevity & Aging
aging decreases cellular NAD+
In plain terms: Does NAD+, a key cellular energy molecule, fall with age?
Part of: • Aging
Yes, agreed across many labs, though it's an observed link and the human drop varies by tissue.
📅 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: Population patterns (Observational)
How the studies fall
What the evidence shows
Tissue/blood NAD+ falls with age across multiple independent labs - one of Sinclair's better-evidenced premises, though the human magnitude is heterogeneous and tissue-specific (more robust in rodents).
The evidence (15)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Migliavacca 2019 · Nat Commun | observational | mixed | moderate | Muscle NAD+ biosynthesis (NAMPT) and mitochondrial capacity reduced in human sarcopenia across three independent cohorts (n=119) |
| Benjamin 2024 · Nutrients | observational | supports | low | Reviews NMN trials; notes age-related NAD+ decline is real but human magnitude is variable and inconsistently measured |
| Yusri 2025 · npj Metab Health Dis | observational | supports | low | Review synthesizing multi-lab evidence that tissue NAD+ metabolism declines with age and modulates mitochondrial function |
| Zhu 2018 · Front Aging Neurosci | observational | supports | low | In-vivo 31P-MRS finds intracellular NAD+ and NAD+/NADH redox decline in the aging human brain |
| Katsyuba 2018 · Nature | animal | tested-null | moderate | De novo NAD+ synthesis (ACMSD inhibition) raises NAD+ and improves mitochondrial function - supports functional importance of declining NAD+ |
| Chini 2020 · Nat Metab | animal | supports | moderate | CD38 ecto-enzyme rises in aging immune cells and drives age-related NAD+ and NMN decline - mechanism for tissue NAD+ fall |
| Tran 2022 · JAIDS | observational | supports | low | [FT-verified] JAIDS 2022 muscle NAD decline driven by HIV/HCV/CMV NOT age; tangential confounded-by-infection |
| Roichman 2021 · Nat Commun | animal | supports | moderate | SIRT6 over-expression restores NAD+-linked energy homeostasis and extends healthy lifespan in mice - supports declining NAD+ economy with age |
| Cuenoud 2020 · Front Aging Neurosci | observational | tested-null | low | In-vivo 31P-MRS shows brain NAD declines and tracks ATP production in humans - independent human measurement of NAD decline |
| Oblong 2020 · Aging Cell | observational | tested-null | low | Aging human skin shows declining mitochondrial/metabolic output; nicotinamide restores integrity - consistent with cutaneous NAD+ decline |
| Bertoldo 2020 · Cell Rep | animal | supports | moderate | Oocyte NAD+ falls with reproductive aging in mice; NAD+ repletion rescues fertility - tissue-specific age decline |
| de Picciotto 2016 · Aging Cell | animal | tested-null | moderate | NMN supplementation reverses age-associated vascular dysfunction in mice, consistent with an age-related NAD+ deficit |
| Elhassan 2019 · Cell Rep | RCT | mixed | low | [FT-verified] Elhassan 2019 NR RCT raises muscle NAD+ but human age-decline data sparse; indirect |
| Chubanava 2023 · Exp Gerontol | mechanism | supports | low | [FT-verified] Chubanava 2023 REVIEW citing PRECLINICAL NAD decline not observational; regrade->mechanism ANIMAL-derived |
| Massudi 2012 · PLoS ONE | observational | supports | moderate | [FT-verified] Massudi 2012 direct human tissue NAD+ neg correlated with age + PARP/oxidative link |
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