NAD+, explained

NAD+ has become one of the most talked-about molecules in wellness — which is striking for a compound biochemists have known for more than a century. NAD+ is not a drug, a peptide, or a hormone: it is a coenzyme, a working part of your own cellular machinery, present in every living cell. This guide explains what NAD+ actually does, why researchers pay attention to how levels change with age, and the difference between NAD+ precursors and NAD+ itself.

What NAD+ is

NAD+ stands for nicotinamide adenine dinucleotide. It is a coenzyme — a helper molecule that enzymes require to do their jobs — found in every living cell, from bacteria to humans. Your body builds it from dietary precursors in the vitamin B3 family, and no cell can run without it: the processes it participates in sit at the center of metabolism itself.

Job one: carrying electrons for energy production

The best-understood role of NAD+ is as an electron carrier. When cells break down food, the energy is extracted in the form of electrons — and NAD+ is the shuttle that picks them up (becoming a form called NADH) and delivers them to the mitochondrial assembly line that produces ATP, the cell's usable energy currency. In this role NAD+ is not used up; it cycles continuously between its two forms, back and forth, like a ferry.

Job two: being consumed by repair and regulation enzymes

The second role is different in kind, and it is the one behind most of the current scientific interest. Several families of enzymes do not merely borrow NAD+ — they consume it, breaking the molecule apart as part of their work. Two get the most attention: sirtuins, enzymes involved in regulating gene expression and cellular housekeeping, and PARPs, enzymes central to DNA repair. Every time these enzymes act, the cell's NAD+ pool gets a little smaller and must be rebuilt.

That consumption is why NAD+ availability matters in a way it wouldn't if the molecule only cycled: demand from repair and regulation draws on the same finite pool that the energy-carrying role depends on.

What researchers observe about NAD+ and age

Research consistently observes that cellular NAD+ levels tend to decline with age. Why that happens — rising consumption, falling production, or both — and what it means are active research questions. It is honest to say this is one of the most actively studied areas of cellular biology right now; it is equally honest to say that NAD+-related therapies are not established treatments for aging or any disease.

That distinction matters. Everything above is a description of biochemistry and of open research — not a claim that raising NAD+ produces any particular result. Whether an NAD+-related therapy makes sense for you is a determination only a licensed provider can make, based on your health history and evaluation.

Precursors versus NAD+ itself

Two different lanes exist here, and they are often conflated. Precursors — compounds in the vitamin B3 family such as nicotinamide riboside or NMN, usually taken orally — are raw material: the cell converts them into NAD+ through its own salvage pathway. Direct NAD+ administration, by injection or infusion, supplies the finished molecule itself. These are mechanistically different approaches, and describing them side by side is not a claim that either is superior — that, too, is a conversation for a provider.

What protocols generally look like

Prescribed NAD+ protocols are typically built around injection or infusion. Beyond that generality, the specifics — dose, frequency, duration, and whether NAD+ is appropriate for you at all — are individualized decisions made by the prescribing provider. Nothing in this article should be read as a dosing recommendation, and a source that offers a one-size-fits-all NAD+ regimen without a provider involved is a warning sign, not a shortcut.

Compounding status: what to know

Injectable NAD+ is available through compounding pharmacies. At Peptivik, it is prepared for individual patients by state-licensed US 503A compounding pharmacies when prescribed by a licensed provider. Compounded medications are not FDA-approved and are not reviewed by the FDA for safety or efficacy — and NAD+ is not FDA-approved for wellness or lifestyle uses. The pharmacies preparing it are subject to state board of pharmacy oversight and USP sterility, endotoxin, and potency standards — a different regulatory lane than FDA premarket review, and one you should expect any honest platform to disclose plainly.

Questions worth asking a provider

• Whether an NAD+-related therapy fits your health history and goals in the first place.
• How they think about precursors versus direct NAD+ administration, and why.
• What they would want to evaluate or monitor before and during treatment.
• How they read the current state of the research — and what they consider unknown.

The bottom line

NAD+ is a coenzyme with two jobs: ferrying electrons for the production of cellular energy, and being consumed by the enzymes that handle DNA repair and cellular regulation. Research observes levels declining with age, and the field studying what to do about that is active but young. As with any prescription therapy, whether NAD+ belongs in your protocol is a decision that belongs with a licensed provider.