Study Finds Whole-Blood NAD+ Levels Stable Across Age Groups

A new study has found that whole-blood NAD+ levels do not decline with age, contradicting a widely held view in aging research. Researchers used a rigorously validated ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry system that accounts for real-world analytical variability.

They quantified NAD+ across seven independent human cohorts and reported that levels remain remarkably stable with age. The same measurements showed stability across various lifestyle interventions. Levels did change as expected in response to nicotinamide riboside supplementation.

The authors stated that the results challenge the utility of blood NAD+ levels as a biomarker of ageing or lifestyle factors. The study was published in Nature on May 14, 2026.

The research team emphasized the importance of their analytical approach after noting inconsistent findings in prior human blood studies. Previous work had proposed that NAD+ levels in blood and tissues decline with age, a claim often cited as rationale for supplementation.

" The new data showed no such age-related drop in whole blood.

NAD+ levels rose following nicotinamide riboside supplementation, consistent with established biochemical pathways. Individual-level data from a twin-pair supplementation study were not made public because of privacy rules under GDPR but can be requested subject to institutional approval.

All other data supporting the findings are included in the article and its source data files. The study lists multiple prior papers that had reported conflicting or supporting associations between NAD+ and age.

The paper references earlier studies that had linked NAD+ abundance to healthy aging and muscle function as well as work that found reduced NAD+ in specific patient groups such as very old patients hospitalized for heart failure. The new results indicate that whole-blood measurements may not reflect those tissue-specific or disease-specific changes.