nadplus.digital

Can NAD+ be measured reliably in blood?

In research, NAD+ can be measured in whole blood. Normal values in humans are so far little known. What a single value means for health is open.

October 2026

What are the key points in brief?

How is NAD+ measured in blood?

Studies measure NAD+ in whole blood with different methods:

NAD+ and its precursors are unstable and difficult to measure in blood1. On a dried blood spot card, at least 85 percent of the value was retained for two weeks at 4 °C1.

In plasma, NAD+ is about 500 times lower than in certain white blood cells. Longer centrifugation and rapid braking of the centrifuge lowered the measured value5.

What does a single measured value tell you?

In a group of 1,518 adults, the mean whole-blood value was 33.0 ± 5.5 µmol/L. Men had higher values than women2. Such a mean describes a particular group. The study does not report it as a reference range for interpreting individual values.

According to a 2026 paper, normal values of NAD and related substances in humans are so far not well known3. A study with seven cohorts found the whole-blood value stable across age and under lifestyle interventions. The authors question the usefulness of the blood value as a marker of age or lifestyle4.

What does a rise after NR or NMN show?

NR and NMN reliably raise NAD-related values in blood. According to a review, this shows biological activity. Clinical efficacy for anti-aging and wellness remains open6.

How much the value rises differs from person to person. One study found a rise of four to six times after NAD+ boosters, depending on the person3.

What can an NAD+ measurement do in a doctor's appointment?

With persistent fatigue, a conversation, a physical examination and simple lab tests come first. According to a review, further tests are needed only with additional symptoms or findings7. An NAD+ measurement would hardly replace this work-up.

The French National Academy of Medicine does not consider measuring biological age advisable for clinical practice on current knowledge8.

More on the work-up is on the page What can lie behind fatigue before considering NAD+ infusions?.

Which sources does this page rely on?

  1. Matsuyama R et al. (2022). Stabilization and quantitative measurement of nicotinamide adenine dinucleotide in human whole blood using dried blood spot sampling. Analytical and Bioanalytical Chemistry. DOI: 10.1007/s00216-022-04469-7

    The study develops a simple measurement of NAD+ from a few drops of whole blood on dried blood spot cards. It is a methods study on calibration and sample stability. NAD+ stayed largely stable on the cards for a limited time, which may make measurement easier.

  2. Yang F et al. (2022). Association of Human Whole Blood NAD+ Contents With Aging. Frontiers in Endocrinology. DOI: 10.3389/fendo.2022.829658

    The study asks whether whole-blood NAD+ declines with age. It is a cross-sectional study of 1,518 adults from a community in China. A decline with age appeared only in men, which may point to differences between the sexes.

  3. Euro L et al. (2026). Dynamics of blood NAD and glutathione in health, disease, aging, and under NAD+-booster treatment. Redox Biology. DOI: 10.1016/j.redox.2026.104343

    The study developed a standardised measurement of NAD and glutathione from a single whole-blood sample. It is a methods and cohort study with 299 healthy adults. Levels appeared stable with age and rose to a different extent from person to person under NAD+ boosters.

  4. Trętowicz MM et al. (2026). Human whole-blood NAD+ levels do not vary with age or lifestyle interventions. Nature Metabolism. DOI: 10.1038/s42255-026-01537-5

    The study tests whether whole-blood NAD+ changes with age or with lifestyle interventions. It used a validated mass spectrometry method in seven independent cohorts. Levels stayed largely stable and changed with nicotinamide riboside, which may call into question blood NAD+ as a marker of ageing.

  5. Saqr AHA et al. (2024). Optimized protocol for quantification of extracellular nicotinamide adenine dinucleotide: evaluating clinical parameters and pre-analytical factors for translational research. Frontiers in Medicine. DOI: 10.3389/fmed.2023.1278641

    The study examines which steps in blood collection and sample handling affect the measurement of NAD+ in plasma. It is a pre-analytical study on human blood samples. Long or fast-braking centrifugation lowered the measured values, which suggests these steps should be standardised.

  6. Gallagher C, Emmanuel OO (2026). NAD⁺ supplementation for anti-aging and wellness: A PRISMA-guided systematic review of preclinical and clinical evidence. Ageing Research Reviews. DOI: 10.1016/j.arr.2026.103057

    The review asks what studies on NAD+ products show for ageing and well-being. It systematically assesses 113 studies, 33 of them in humans. NR and NMN may raise NAD levels and appear well tolerated, while a clinical benefit remains open, and suitable trials of NAD+ infusions were lacking.

  7. Maisel P, Baum E, Donner-Banzhoff N (2021). Fatigue as the Chief Complaint. Deutsches Ärzteblatt International. DOI: 10.3238/arztebl.m2021.0192

    The paper summarises how family doctors may assess persistent fatigue. It is a review based on a literature search. Its authors suggest that history, physical examination and simple laboratory tests may usually be enough, with further tests mainly when other findings point that way.

  8. Académie nationale de médecine (2026). Approche clinique de la longévité en bonne santé. Report of 13 January 2026, in French. www.academie-medecine.fr/wp-content/uploads/2026/01/RAPPORT-Approche-clinique-de-la-longevite-en-bonne-sante-APRES-VOTE.pdf

    The report asks what medical practice can do today to support a long and healthy life. It is a position paper of the French National Academy of Medicine. Based on current knowledge, it does not recommend measuring biological age or using anti-ageing agents in practice and gives priority to lifestyle.