Tier 2 — strong

Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD + in healthy middle-aged and older adults

Martens CR, Denman BA, Mazzo MR, Armstrong ML, Reisdorph N, McQueen MB, Chonchol M, Seals DR
Nature communications 2018 9; 1; 1286

Bibliography

PubMed
PMID 29599478
PubMed Central
PMC5876407
DOI
10.1038/s41467-018-03421-7
Funding
NIH and Glenn/AFAR support; ChromaDex supplied study materials and partial funding.
Competing interests
The authors declared no competing interests; industry material supply and partial support were disclosed.

Study snapshot

DesignRandomized placebo-controlled human trial
ModelHuman participants
Sample30 randomized; 24 completed; ages 55–79 years
InterventionNR chloride 500 mg twice daily versus placebo
DurationTwo 6-week crossover periods
EndpointsTolerability; NAD+ metabolism; exploratory vascular measures

What the study showed, in plain terms

NR raised NAD+ metabolism and was generally well tolerated in this early study of healthy middle-aged and older adults.

Key findings

Blood-cell NAD+ increased by about 60%.

What this study can and cannot tell us

Small crossover trial. Blood-pressure and arterial-stiffness findings were exploratory and require adequately powered confirmation.

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Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology