Blood NAD+ Levels Stay Flat With Age, Challenging Popular Aging Theory
Based on: Human whole-blood NAD+ levels do not vary with age or lifestyle interventions.
One of the most repeated ideas in longevity is that NAD+ declines as we age, a story that helped make NR and NMN household names in the space. This large, carefully controlled study takes a closer look. Across seven independent cohorts and more than 300 people, researchers found that whole-blood NAD+ levels stayed remarkably stable with age, and didn't shift meaningfully in response to exercise, protein-rich diets, or multimodal lifestyle interventions in older adults. Importantly, NR supplementation did raise blood NAD+ as expected, confirming that the supplements work pharmacologically, the question is just whether blood NAD+ is the right thing to be measuring in the first place.
Key Insight
This study suggests blood NAD+ tests may not reliably reflect biological age.
Original Paper
Trętowicz MM, Scantlebery AML, Schomakers BV, Eroğlu KD, van Weeghel M, Spek V, Vinten KT, Legon L, Coskun E, Millan-Domingo F, Olaso-Gonzalez G, Gomez-Cabrera MC, Montoro-García S, Noguera-Navarro C, van Kuilenburg ABP, Moco S, van Hattum JC, Jørstad HT, Benali M, van der Helder J, Biersteker EJM, Muniandy M, Pietiläinen KH, Pirinen E, Slagboom PE, Beekman M, Deelen J, Zapata-Pérez R, Weijs PJM, Tieland M, Janssens GE, Houtkooper RH
Conflict of Interest Disclosure: Authors declare no competing interests.
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Disclaimer: Research summaries are provided for informational purposes only and do not constitute medical advice. Always consult a qualified healthcare professional before making changes to your health routine.