Nicotinamide adenine dinucleotide (NAD+) is a coenzyme found in every cell of the body. It plays a central role in energy production, DNA repair, and cellular health. NAD+ levels naturally decline with age, which has led to growing interest in NAD+ supplements and injections as part of wellness and healthy aging routines.

If you’ve come across the term NAD+ in conversations about energy, longevity, or cellular health, you’re not alone. Interest in NAD+ has grown steadily as researchers explore its role in how the body produces energy, repairs cells, and responds to stress.

Nicotinamide adenine dinucleotide (NAD+) is a coenzyme — a molecule that helps enzymes do their jobs — found in every living cell. It’s involved in hundreds of metabolic reactions, and without it, cells would struggle to function. NAD+ levels tend to decline as people age, which has prompted interest in ways to support those levels through supplements, injections, or intravenous (IV) therapy.

Discover what NAD+ is, what it does in the body, why levels change over time, and what to know before considering NAD+ therapy.

What is NAD+?

NAD+, short for nicotinamide adenine dinucleotide, is a coenzyme that works alongside enzymes in nearly every cell of the body. A coenzyme is a helper molecule — it doesn’t act on its own, but it enables other biological processes to happen.

NAD+ is made up of two nucleotides (the building blocks of DNA and RNA) joined together. It exists in two forms: NAD+, the oxidized form, and NADH, the reduced form. These two forms cycle back and forth as the molecule accepts and donates electrons during metabolic reactions, which is central to how cells produce energy.

The body produces NAD+ from several sources, including:

• Tryptophan, an amino acid found in foods like turkey, eggs, and dairy
• Niacin (vitamin B3), found in meat, fish, and fortified foods
• Nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN), compounds that have become popular as NAD+ precursor supplements

What does NAD+ do in the body?

NAD+ is involved in a wide range of biological processes. Here are some of the key roles it plays.

The following describes well-established roles of NAD+ at the cellular level. Research into what supporting NAD+ levels through therapy means clinically is still ongoing, and many potential applications have not yet been confirmed in large-scale human trials.

1. Energy metabolism

The most well-known function of NAD+ is its role in producing cellular energy. Inside cells, a process called cellular respiration converts nutrients from food into adenosine triphosphate (ATP) — the molecule cells use for energy. NAD+ is an essential participant in this process, carrying electrons through key metabolic pathways, including glycolysis and the citric acid cycle.¹

NAD+ participates in the metabolic pathways cells use to generate ATP, making it a fundamental component of cellular energy production.¹

2. DNA repair

NAD+ is required by a group of enzymes called PARPs (poly ADP-ribose polymerases), which detect and help repair damage to DNA. DNA damage occurs constantly from normal cell processes, environmental exposure, and aging. PARPs use NAD+ as a substrate to do their repair work, which means that NAD+ availability can influence how well the body maintains its genetic material.²

3. Sirtuins and aging-related processes

NAD+ also activates a family of proteins called sirtuins, which are involved in regulating cellular stress responses, inflammation, metabolism, and gene expression. Research has linked sirtuin activity to processes associated with healthy aging, including mitochondrial function and cellular repair.² Sirtuins require NAD+ to function, which is one reason NAD+ has become a topic of interest in longevity research.

4. Mitochondrial function

Mitochondria are the structures inside cells responsible for energy production. NAD+ plays a critical role in maintaining healthy mitochondrial function. Mitochondrial health is closely linked to overall cellular health, and decline in mitochondrial function is associated with aging and certain chronic conditions.¹

5. Circadian rhythm regulation

Research has suggested that NAD+ metabolism is connected to the body’s internal clock, or circadian rhythm. NAD+ levels naturally fluctuate throughout the day in a pattern that aligns with the body’s circadian cycle, and researchers are studying what this relationship means for metabolic timing.²

Why do NAD+ levels decline with age?

NAD+ levels in the body naturally decrease as people get older. Studies have observed significant declines in NAD+ levels in various tissues during aging, with some research suggesting levels can drop by as much as 50% between middle age and older adulthood.²

Several factors may contribute to this decline:

• Increased activity of NAD+-consuming enzymes (such as PARPs and CD38) with age
• Reduced efficiency of NAD+ biosynthesis pathways
• Chronic low-grade inflammation, which is associated with aging and can accelerate NAD+ consumption
• Lifestyle factors, including poor diet, sedentary behavior, excess alcohol use, and disrupted sleep

This age-related decline has driven scientific interest in NAD+ metabolism and its relationship to cellular function over time.

What is NAD+ therapy?

NAD+ therapy refers to interventions designed to raise NAD+ levels in the body. The most common forms include:

NAD+ supplements: Oral supplements often contain NAD+ precursors — compounds the body can convert into NAD+. Common precursors include nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). Some products contain niacin or nicotinamide (both forms of vitamin B3), which also serve as NAD+ precursors.

NAD+ injections: Subcutaneous (under the skin) or intramuscular injections may offer a more direct delivery method compared to oral supplements. Some people pursuing NAD+ therapy opt for injections administered through a telehealth or clinical provider.

NAD+ IV therapy: Intravenous (IV) infusions deliver NAD+ directly into the bloodstream. IV therapy is typically done in a clinical setting and takes several hours per session.

It’s important to understand that NAD+ supplements are not drugs. The Food and Drug Administration (FDA) does not approve dietary supplements for safety and effectiveness before they are marketed.³ If you are considering a prescription NAD+ treatment, a licensed provider will determine whether it is medically appropriate based on your individual health history.

What are common NAD+ side effects?

Side effects can occur with NAD+ therapy and vary by person and delivery method. Some commonly reported side effects include:

• Nausea or upset stomach (more common with oral supplements and IV infusions)
• Flushing or skin redness (particularly with niacin-based supplements)
• Fatigue or brain fog, especially early in IV therapy
• Injection site reactions (redness, soreness, bruising) with injectable forms

A licensed provider can review your medical history, current medications, and potential risks before recommending any form of NAD+ therapy. Seek medical care for severe or concerning symptoms.

How LumiMeds Can Help

If you’re curious about NAD+ injections or NAD+ therapy, LumiMeds connects eligible patients with licensed providers who can review their health history and treatment goals to determine whether prescription NAD+ treatment may be medically appropriate. If prescribed, medication may be fulfilled through licensed pharmacy partners and shipped directly to you.

Start your online assessment to see if you may be a candidate for NAD+ care through LumiMeds.

Key Takeaways

• NAD+, or nicotinamide adenine dinucleotide, is a coenzyme found in every cell that is essential for energy production, DNA repair, and cellular health.
• NAD+ levels naturally decline with age, which has led to growing interest in supplements, injections, and IV therapy as ways to support those levels.
• NAD+ plays a key role in mitochondrial function, sirtuin activation, and circadian rhythm regulation, all of which are tied to healthy aging research.
• NAD+ supplements are not FDA-approved and have not been evaluated by the FDA for safety, efficacy, or quality before marketing.
• A licensed provider can help determine whether NAD+ therapy may be appropriate for your individual health situation.

FAQs

What does NAD+ do for the body?

NAD+ is a coenzyme involved in hundreds of metabolic reactions. Its primary roles include helping cells produce energy (ATP), supporting DNA repair through PARP enzymes, activating sirtuins involved in stress response and aging-related processes, and maintaining mitochondrial function. Without NAD+, cells cannot carry out the basic processes needed to function normally.

Does NAD+ actually work?

Research on NAD+ is ongoing and growing. Studies have demonstrated that NAD+ plays essential roles in cell biology, and some preclinical and human studies have explored the effects of raising NAD+ levels through precursor supplementation. However, many of the potential benefits seen in animal models have not yet been confirmed at scale in human clinical trials. It’s best to discuss what the current evidence means for your specific health goals with a licensed provider.

What is the difference between NAD and NAD+?

NAD (nicotinamide adenine dinucleotide) is the general name for the molecule. NAD+ refers specifically to its oxidized form, which is the active form involved in accepting electrons in metabolic reactions. NADH is the reduced form (it has gained an electron). When people talk about NAD+ therapy or supplements, they are typically referring to efforts to increase the NAD+ form in the body.

What are the signs of low NAD+ levels?

There is no standard clinical test to measure NAD+ deficiency in routine medical care. However, general signs associated with declining cellular energy and metabolic function — such as persistent fatigue, reduced cognitive clarity, slower recovery, and poor sleep quality — are sometimes discussed in the context of low NAD+. These symptoms can have many causes, so it is important to speak with a healthcare provider for a proper evaluation.

Is NAD+ the same as vitamin B3?

They are related but not the same. Vitamin B3 (niacin) is a precursor to NAD+ — meaning the body can use it to produce NAD+. Other precursors include nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). NAD+ is the finished coenzyme that the body uses in metabolic processes, while vitamin B3 is one of several starting materials.

What is NAD+ IV therapy?

NAD+ intravenous (IV) therapy involves delivering NAD+ directly into the bloodstream through an IV line. It is typically administered in a clinical setting and can take several hours per session. Some people pursue IV therapy because it bypasses digestion and may allow for more direct delivery compared to oral supplements. A licensed provider should be consulted to determine whether IV therapy is appropriate for you.

Compounded medications are not FDA-approved and have not been evaluated for safety and effectiveness by the FDA. Compounded medications are not brand-name drugs nor are they considered “generics.” Compounded medications are prepared by state-licensed compounding pharmacies or federally registered outsourcing facilities.

Payment does not guarantee the writing or dispensing of a prescription. A licensed provider will determine whether treatment is medically appropriate based on individual health history and needs.

This information is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a licensed healthcare provider with any questions you may have regarding a medical condition or treatment.

Sources

1. Yusri, K., et al. “The role of NAD+ metabolism and its modulation of mitochondria in aging and disease.” npj Metabolic Health and Disease. https://pmc.ncbi.nlm.nih.gov/articles/PMC7963035/
2. Covarrubias, A. J., Perrone, R., Grozio, A., & Verdin, E. “NAD+ metabolism and its roles in cellular processes during ageing.” Nature Reviews Molecular Cell Biology. https://pmc.ncbi.nlm.nih.gov/articles/PMC12177089/
3. Food and Drug Administration. “Is It Really ‘FDA Approved’?” https://www.fda.gov/consumers/consumer-updates/it-really-fda-approved