Nicotinamide adenine dinucleotide (NAD⁺) is one of the most important and often overlooked coenzymes in the body. Present in every living cell, NAD⁺ fuels core biochemical reactions: converting nutrients into energy, repairing damaged DNA, modulating inflammation, and sustaining mitochondrial function. In functional medicine, it’s emerging as a valuable biomarker of metabolic health and biological resilience and as central player in longevity protocols and cellular energy optimization.
Across anti-aging clinics, metabolic optimization protocols, and IV lounges, NAD⁺ is being positioned as both a therapeutic target and a marker of deeper dysfunction. When a video of Hailey Bieber and Kendall Jenner receiving NAD⁺ IV drips went viral, it became a patient talking point.
Practitioners must be prepared not only to explain what NAD⁺ is but to assess when these therapies are relevant, how they work, and what the scientific evidence supports.
Here's what you'll find in this article:
What NAD⁺ Does
Think of NAD⁺ as a molecular currency—constantly traded to fuel energy metabolism, protect genetic integrity, and manage inflammation. "Declining NAD⁺ is one of the earliest molecular hallmarks of aging" according to Dr. Ivan Rusilko of Lifestyle Medicine Miami in his American Academy of Anti-aging Medicine (A4M) Spring Congress 2025 presentation on The Business of Diagnostics. When NAD⁺ levels decline, mitochondrial efficiency falters, oxidative damage builds, and cellular stress responses weaken.
Clinical roles of NAD⁺ include:
- Sirtuin activation: Regulates genomic stability, autophagy, and inflammation resolution
- Mitochondrial respiration: Essential for oxidative phosphorylation and ATP synthesis
- Neuroinflammatory control: Affects cognition, mood, and neuroplasticity
- Insulin sensitivity: Supports lipid metabolism and metabolic flexibility
Why NAD⁺ Declines
By the time a 38-year-old patient walks into your office with fatigue, brain fog, or unexplained metabolic slowdown, their NAD⁺ may have been on the decline for years, long before their symptoms surfaced.
Understanding why this coenzyme drops so precipitously with age, stress, or toxic exposure helps reframe these complaints not just as diagnoses to treat—but as energy disruptions to recalibrate.
Main drivers of depletion include:
- Chronic inflammation or immune overactivation
- Circadian disruption, poor sleep, or stress
- Exposure to toxins (e.g., mold, heavy metals)
- Alcohol overuse or metabolic overload
- Age-related decline in NAD⁺ biosynthesis
“Any disease or combination of stressors—from toxin exposure to trauma—can impair mitochondrial capacity, And that capability isn’t just about producing ATP—it also regulates about 80% of the body’s reactive oxygen species (ROS). Too much or too little ROS can trigger immune imbalance."
- Dr. Mitch Ghen, Director of Physician Consultations, Access Medical Labs
NAD⁺ reflects how well a patient can make energy, resist stress, and maintain cellular repair. In functional medicine, this makes it a compelling early biomarker for preventive and performance-based care.
Where NAD⁺ Testing Fits in Functional Medicine
This is not a disease-detection test. It’s a performance marker—a window into how well your patient’s cells are functioning.
NAD⁺ testing may be most useful for:
- Evaluating NAD⁺ precursor protocols (NMN, NR, IV NAD⁺)
- Supporting mitochondrial health in fatigue syndromes
- Addressing neuroinflammatory decline or cognitive concerns
- Monitoring metabolic resilience in toxin exposure or oxidative stress
- Optimizing outcomes in GLP-1 therapy or athletic performance
In functional and integrative care models, NAD⁺ is rarely a solo marker—it’s part of a wider clinical picture that spans energy metabolism, detox capacity, cognitive health, and longevity.
Related Video: The NAD+/NADH ratio's Role in Mitochondrial and Metabolic Health
| Use Case | Pair With | NAD⁺ Role |
| Fatigue & Mitochondrial Dysfunction | Organic Acids, CoQ10, Oxidative Stress Markers | Supports ATP production and cellular energy |
| GLP-1 Therapy Optimization | Insulin, Glucose, Lipids, Hormones | Monitors metabolic resilience under appetite-suppressing regimens |
| Neuroinflammatory Syndromes | Cortisol, DHEA, Neurotransmitters, CRP | Assesses cellular repair and sirtuin-related brain health |
| Detox Support & Mold Illness | Glutathione, Heavy Metals, Inflammatory Markers | Tracks ability to recover from oxidative or immune burden |
By anchoring NAD⁺ to broader assessments, clinicians can use it to personalize protocols—whether for high performers, patients in recovery, or those with chronic metabolic stress.
Related Video: How Mitochondrial Damage Contributes to Chronic Illness
Applying NAD⁺ Concepts in Clinical Practice
NAD⁺ connects the dots between aging, inflammation, and cellular energy. It provides a compelling framework for understanding metabolic flexibility and performance optimization. Clinicians can address NAD+ optimization through evidence-based strategies, including targeted lifestyle interventions, and protocols addressing sleep, stress, and toxin load.
By focusing on upstream drivers of NAD⁺ depletion and downstream indicators of cellular performance, clinicians can personalize strategies that align with prevention, vitality, and healthy aging.
References:
- Covarrubias AJ, Perrone R, Grozio A, Verdin E. NAD⁺ metabolism and its roles in cellular processes during ageing. Nature Reviews Molecular Cell Biology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7352804/
- Imai S, Guarente L. NAD⁺ and sirtuins in aging and disease. Trends in Cell Biology.. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6520897/
- Rajman L, Chwalek K, Sinclair DA. Therapeutic potential of NAD⁺-boosting molecules: the in vivo evidence. Cell Metabolism https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8837905/
- Rusilko I. Dr. Ivan Rusilko on NAD+ Benefits for the human body | Lifestyle Medicine.https://www.youtube.com/watch?v=ZBSzm_i9QZU
- How mitochondrial damage contributes to chronic illness. True Health News. https://www.youtube.com/watch?v=xv6Fs27TKF4
- NAD⁺/NADH ratio and metabolic health. True Health News. https://www.youtube.com/watch?v=mEw5X1fDVf4
- Verdin E. NAD⁺ in aging, metabolism, and neurodegeneration. Science. https://pubmed.ncbi.nlm.nih.gov/25131149/
About Access:
Access is the nation’s premier specialty diagnostic lab. We offer a broad menu of testing from blood, saliva, urine & swab samples. We perform all of your tests in our 25,000 sq. ft. ultra-automated facility in Jupiter, Florida & provide results within 24hrs. Since 2003, we continuously strive to innovate, inspire, and improve solutions for physicians by providing an exceptional personalized experience with the most accurate testing.
Feel free to contact our specialist to find out more about prices and services. We are always ready to answer your questions: sales@accessmedlab.com
V
Share:
Unlocking Profit in Longevity Healthcare
Why 2025 Is a Turning Point for Functional Medicine
