Half the longevity internet will tell you to "test your NAD+ levels" and track them like a number on a standard blood panel. The evidence is more careful. You can measure NAD+ in blood, and researchers do it in clinical trials using specialized lab assays, but there is no standardized, validated at-home or routine clinical NAD+ blood test sold to consumers, no agreed-upon normal range to compare yourself against, and no proven link between a single NAD+ number and how you feel or age. Right now, measuring NAD+ is a research tool, not a personal diagnostic.
Key takeaways
- NAD+ can be measured in blood and tissue, but only with specialized lab methods used in research, not a test you can reliably order for yourself.
- There is no FDA-cleared consumer NAD+ blood test with a validated reference range, and no established healthy number to aim for.
- In trials, NAD+ precursors increased blood NAD+, but that group-level finding does not translate into a meaningful personal readout.
- For now, consistency, sensible dosing, and a transparent, third-party-tested product matter more than chasing a number.
Can you actually measure NAD+ in blood?
Yes, in a laboratory. NAD+ (nicotinamide adenine dinucleotide) is present in blood and in every tissue, and researchers quantify it using sensitive techniques such as liquid chromatography-mass spectrometry and enzymatic assays. These are the methods behind the research you read about whether NAD+ changes with age, or rises with supplementation. They are precise, but they are also expensive, technically demanding, and run in controlled research settings, not the kind of turnkey panel your primary-care lab hands you at a checkup.
The clinical trials in this field make the point. A 2018 randomized, placebo-controlled trial found that the NAD+ precursor nicotinamide riboside was well tolerated and increased blood NAD+ in healthy middle-aged and older adults, a number that exists only because researchers drew blood and measured it in a lab. Later trials did the same with NMN: a 2023 dose-finding study in 80 healthy adults measured blood NAD+ directly and showed it rose in a dose-dependent way, and a separate placebo-controlled trial in adults aged 55 to 70 found that 500 mg of NMN, the same daily dose CELLSHE uses, raised whole-blood NAD+ from about 24 to 42 micromoles per liter. In other words, NAD+ is measurable, when a research team with the right equipment does the measuring.
Is there a NAD+ blood test I can buy?
Not in any standardized, validated sense. A few specialty labs and direct-to-consumer kits market NAD+ testing, but the category has real gaps:
- No FDA-cleared consumer test. There is no FDA-cleared consumer NAD+ blood test and no agreed reference range.
- Little standardization. Methods differ between labs, so two results may not be comparable.
- It depends what is measured. Whole blood, plasma, and the NAD+ inside specific cells are not the same thing.
- CLIA is not validation. A lab may be CLIA-certified, which means its testing process meets federal quality standards. It does not mean there is a validated personal reference range for NAD+, or an established meaning for your individual number.
There is also a practical catch that trips up even good labs: NAD+ is chemically unstable and begins to break down quickly once blood is drawn, so a sample has to be collected, chilled, and processed carefully or the reading drifts. That fragility is one reason NAD+ measurement has stayed in the research world rather than becoming a routine test. If you have seen a slick "know your NAD+ age" offer, treat the precision it implies with healthy skepticism.
What would a NAD+ number even tell you?
Less than the marketing suggests. Even a clean, accurate NAD+ reading has no validated target to compare against, and no established relationship between one person's blood NAD+ level and their health, energy, or rate of aging. Levels vary by tissue, by time of day, and by assay, so a single figure is hard to interpret on its own.
The trial data show the gap. Even where a study reports that NMN raised blood NAD+, that is an average across a group in a controlled study, not a personal diagnostic you can act on. Knowing a trial moved a biomarker on average is not the same as knowing your own number means anything for you.
Better questions than "what's my number?"
If a validated NAD+ test is not available, what is actually useful? For most people, the productive questions are about the routine, not the readout:
- Are you taking a disclosed, sensibly dosed form? Known ingredients at doses you can check against the research.
- Is the product third-party tested, with a Certificate of Analysis you can verify?
- Are you consistent over months, rather than chasing a quick change?
Those are the inputs you can control, and they matter more right now than a number no one can yet interpret for you. If you want a simple, no-blood starting point for thinking about your cellular-health habits, our free Cellular Age Check is a 2-minute self-assessment: take the free Cellular Age Check →.
What we know, and what we don't
What we know: NAD+ can be quantified in blood and tissue with laboratory assays, and those assays are how trials show NAD+ precursors like NMN and nicotinamide riboside increase blood NAD+ on average. In older men with sarcopenia across three ethnicities, muscle NAD+ and the enzymes that produce it were measurably reduced versus age-matched healthy controls, even though whole-blood NAD+ itself does not clearly fall with age.
What we don't know: whether any single person's blood NAD+ level predicts their health or how they age, what a normal or optimal number would be, and whether tracking NAD+ over time changes any decision worth making. The consumer testing has run ahead of the science that would make it meaningful.
What a NAD+ test will not do
To keep this honest: a NAD+ test, even a good one, is not a medical test, will not reveal your biological age, will not prove whether a supplement is working for you, and will not replace a conversation with your own clinician. Anyone selling a NAD+ number as a verdict on your health is offering more certainty than the science currently supports. If you are considering testing or supplementing for a specific health concern, talk to your clinician first.
Where CELLSHE fits
We build supplements for people who want an evidence-informed, anti-hype routine, not a number to obsess over. If your goal is to support your body's own NAD+ biosynthesis, NMN is the precursor with the human-trial evidence behind it, which is why our NMN 500 → delivers high-purity β-NMN at a daily dose that sits within the range studied in placebo-controlled trials.* Our NAD+ → formula (500 mg NAD+ with 250 mg quercetin and 150 mg trans-resveratrol, $59 or $49 monthly) does a different job: antioxidant and polyphenol support alongside everyday cellular vitality.* A Certificate of Analysis is available on the product page or on request.
We will not promise either product moves a lab value you can check at home, because a validated consumer test for that does not meaningfully exist yet. What we promise is a clean, honestly labeled product and the context to decide for yourself. If you want the bigger picture, our guide to NAD+ supplements: what actually works → and our explainer on what NAD+ is and how it works → are honest places to start, and if you are weighing the two most common precursors, our NMN vs NR comparison → breaks down the difference.
Frequently asked questions
Can you test your NAD+ levels at home?
There is no standardized, validated at-home NAD+ blood test with an established reference range. Some direct-to-consumer kits exist, but methods aren't standardized and NAD+ degrades quickly after a sample is taken, so results are hard to interpret and compare.
How do researchers measure NAD+?
In studies, NAD+ is measured with sensitive laboratory techniques such as liquid chromatography-mass spectrometry or enzymatic assays, on carefully handled blood or tissue samples. These methods are precise but require specialized equipment and controlled sample handling.
Is there a normal or optimal NAD+ level?
Not one that has been validated for individuals. NAD+ varies by tissue, time of day, and assay, and no agreed reference range or personal target has been established, which is why a single number is difficult to interpret.
Does a higher NAD+ level mean better health?
There is no proven link between one person's blood NAD+ level and their health or rate of aging. Trials show precursors can increase blood NAD+ on average, but a higher reading has not been shown to translate into a specific benefit for you.
Should I get my NAD+ tested before taking a supplement?
A NAD+ test isn't a reliable way to guide that decision today, since there is no validated consumer test or target. If you are considering a supplement for a specific health reason, talk to your clinician rather than relying on a number.
References
- Martens CR, et al. (2018). Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults. Nature Communications 9:1286. PMID: 29599478. pubmed.ncbi.nlm.nih.gov/29599478
- Yi L, et al. (2023). The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, dose-dependent clinical trial. GeroScience 45(1):29-43. PMID: 36482258. pubmed.ncbi.nlm.nih.gov/36482258
- Randomized, double-blind, placebo-controlled trial of β-NMN in adults aged 55 to 70, reporting whole-blood NAD+ of about 23.8 micromoles per liter on placebo versus 41.7 at 500 mg per day (published alongside a fingerstick NAD+ assay). PMID: 37641521. pubmed.ncbi.nlm.nih.gov/37641521
- Human study measuring whole-blood NAD+ across separate adult age groups: concentrations did not decline with age, and rose with precursor supplementation. PMID: 42135539. pubmed.ncbi.nlm.nih.gov/42135539
- Analysis of muscle NAD+ and NAD+-synthesizing enzymes in older men with sarcopenia across three ethnicities versus age-matched healthy controls. PMID: 31862890. pubmed.ncbi.nlm.nih.gov/31862890
- Review of oral NAD+ supplementation concluding there is no good evidence that intact oral NAD+ raises NAD+ levels. PMID: 37971292. pubmed.ncbi.nlm.nih.gov/37971292
