Intracellular NAD+ Assessment
Nicotinamide adenine dinucleotide (NAD+) is a vital coenzyme found in every cell of your body. It plays a critical role in cellular respiration, helping to convert nutrients into cellular energy (ATP). As we age, or due to chronic stress and metabolic strain, NAD+ levels decline, contributing to cellular fatigue and reduced biological resilience.
Intracellular NAD+ testing evaluates the active levels of NAD+ and NADH inside your cells, giving us the objective biological data needed to optimize cellular function and support longevity.
What Intracellular NAD+ Testing Measures
Rather than estimating NAD+ status indirectly, our testing measures the active NAD+ and NADH levels present inside your cells. This gives an objective baseline of your current cellular energy capacity, rather than relying on symptoms alone to gauge how well your mitochondria are functioning.
How NAD+ Testing Works
Testing begins with a simple blood draw performed in our clinic. Your sample is analyzed to determine intracellular NAD+ and NADH levels, giving a clear picture of your current cellular energy status. Once results are available, you’ll meet with our clinical team to review your findings and discuss whether NAD+ support, such as intravenous NAD+ therapy, may be appropriate for your goals.
Who Should Consider NAD+ Testing
NAD+ testing may be worth considering if you’re experiencing signs consistent with declining cellular energy production, including:
- Persistent fatigue that isn’t explained by sleep or lifestyle factors
- Reduced physical stamina or slower recovery from exertion
- Brain fog or difficulty concentrating
- An interest in proactive, longevity-focused wellness monitoring
- Ongoing NAD+ therapy, where testing helps track response over time
What to Expect
The blood draw itself takes just a few minutes. Results are typically available within several business days, after which you’ll schedule a follow-up consultation to discuss your findings and, if appropriate, a personalized plan to support healthy NAD+ levels going forward.
How a Longevity Center Patient Overcame Symptoms of Anxiety
Luke S., owner of a landscape design and construction company, increasingly felt anxious and depressed, especially in the mornings, with no indication of underlying causes, including from standard blood panels. The onset of afternoon brain fog and general malaise compounded things. The symptoms became debilitating to the point that it became difficult for Luke to accomplish the daily tasks needed for his business to succeed.
Following a comprehensive intake and lab panel, Luke began our personalized male hormone optimization protocol, including testosterone replacement therapy. After just a few appointments, he has regained feelings of motivation and higher energy levels throughout the day, and the afternoon brain fog has subsided completely. Luke insists that the therapies he receives at The Longevity Centers have improved his personal life and enabled his business to thrive.
*While individual outcomes vary and results are not guaranteed for every patient, his experience reflects the kind of root-cause, whole-body approach the clinic aims to offer those for whom conventional treatment alone has fallen short.
Explore Our Greenville, South Carolina Location
Advanced Longevity Medicine Grounded in Evidence-Based Care
At The Longevity Center Greenville, our root-cause wellness blueprints are built strictly on peer-reviewed, data-driven medical science. Our advanced protocols for cellular health, environmental detoxification, and metabolic longevity align directly with research from major global clinical networks. For further reading on the clinical efficacy behind our primary therapy models, we invite you to review public medical data available through the National Institutes of Health regarding cell recovery via NAD+ stabilization, current PubMed / NCBI clinical trials evaluating IV ozone and chelation therapies for systemic inflammation, and the American Osteopathic Association guidelines emphasizing whole-person preventative medical systems.
Serving Greenville with Science-Driven Care
Frequently Asked Questions
What does NAD+ testing measure?
NAD+ testing measures the intracellular levels of NAD+ and NADH in whole blood and calculates the total NAD pool and the NAD+/NADH ratio. Together, these values provide a snapshot of cellular energy status and mitochondrial redox state.
What does the NAD+/NADH ratio tell you?
The NAD+/NADH ratio reflects the cellular redox state, an indicator of how efficiently cells convert nutrients into energy. Because NAD+ tends to fall while NADH rises with age and metabolic stress, the ratio often reveals changes that measuring NAD+ alone would miss, which is why both forms are measured.
Who should consider NAD+ testing?
A physician may recommend NAD+ testing as part of a broader evaluation for unexplained fatigue, exercise intolerance, suspected mitochondrial or metabolic dysfunction, post-viral fatigue, or the assessment of biological aging. It is not a general-population screening test and is interpreted alongside other clinical information.
Can you have too much NAD+?
Yes. While depleted NAD+ is associated with fatigue and metabolic and neurodegenerative patterns, abnormally elevated NAD is not necessarily beneficial and has been associated with metabolic disturbance in the research literature. Healthy bioenergetics reflects a balanced NAD+/NADH ratio rather than the highest possible level, which is one reason measurement and physician interpretation are important.
Is NAD+ testing a diagnostic test?
No. NAD+ testing is a laboratory-developed test that has not been approved or cleared by the FDA, and its results are not intended to be used as a sole means for clinical diagnosis. It provides one measurable data point about cellular energy status that a qualified healthcare provider interprets within a comprehensive evaluation.
If you are interested in understanding your cellular energy and NAD+ status, speaking with a licensed physician about whether NAD+ testing is appropriate for you is an important first step.
This content is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. It describes physiology and does not reference specific services. Individual circumstances vary. Always consult a licensed physician regarding your health.
References
- Covarrubias AJ, et al. “NAD+ metabolism and its roles in cellular processes during ageing.” Nature Reviews Molecular Cell Biology / NIH PMC, 2023. PMC9917998
- McReynolds MR, et al. “Age-related NAD+ decline.” Experimental Gerontology / NIH PMC, 2020. PMC7442590
- Clement J, et al. “The Plasma NAD+ Metabolome Is Dysregulated in Normal Aging.” Redox Biology / NIH PMC, 2019. PMC6482912
- Zhu XH, et al. “In vivo NAD assay reveals the intracellular NAD contents and redox state in healthy human brain and their age dependences.” PNAS 112(9): 2876–2881, 2015. doi:10.1073/pnas.1417921112
- Xu HN, Li LZ. “Quantitative redox imaging biomarkers for studying tissue metabolic state and its heterogeneity.” Journal of Innovative Optical Health Sciences / NIH PMC, 2014. PMC6905396
- Bradshaw PC. “Cytoplasmic and Mitochondrial NADPH-Coupled Redox Systems in the Regulation of Aging.” Nutrients 11(3): 504, 2019. doi:10.3390/nu11030504
- Various authors. “Mitochondrial dysfunction in metabolic and aging disease.” Signal Transduction and Targeted Therapy 10, 2025. doi:10.1038/s41392-025-02253-4
- Various authors. “Insulin resistance: pathophysiology and mechanisms.” NIH PMC, 2025. PMC11942056
Locating Our Wellness Clinic
Our Greenville clinic is located on Wade Hampton Boulevard across from Harris Teeter, near East Stone Avenue and in close proximity to the North Main, Timmons Park, and Cleveland Park neighborhoods.
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