Study of 300 People Challenges N.A.D.+ Anti-Aging Claims
Updated
Updated · The New York Times · May 23
Study of 300 People Challenges N.A.D.+ Anti-Aging Claims
8 articles · Updated · The New York Times · May 23
A Nature Metabolism study analyzing blood samples from more than 300 people across seven data sets found no evidence that N.A.D.+ blood levels decline with age.
That result undercuts a central premise behind popular longevity supplements: the long-held claim that age-related N.A.D.+ depletion helps drive functional decline.
The researchers compared younger and older adults and also included groups ranging from frail individuals to elite athletes; supplements still raised N.A.D.+ levels, but baseline levels did not show an age-linked drop.
A February preprint reached the same conclusion, adding to doubts about a fast-growing supplement market promoted by celebrities, influencers and major retailers despite limited human evidence of anti-aging benefits.
If blood levels are stable, could N.A.D.+ decline in our tissues still be the real key to aging?
Science says blood N.A.D.+ doesn't drop with age. Is the billion-dollar anti-aging industry built on a myth?
A major study published in May 2026 in Nature Metabolism has overturned the long-standing belief that blood NAD⁺ levels always decline with age. By analyzing samples from over 300 healthy people using advanced mass spectrometry, researchers found that whole-blood NAD⁺ remains stable across age groups. This discovery challenges a core idea behind many anti-aging supplements and marks a turning point in NAD⁺ research. The findings have shifted scientific understanding of NAD⁺ metabolism and aging, highlighting the need to rethink how NAD⁺ is measured and its true role in health and disease.