NAD+: What It Is and What It Does

What NAD+ is

NAD+ (nicotinamide adenine dinucleotide) is not a peptide — it's a coenzyme, a helper molecule that every cell uses to produce energy. It is supplied as an analytical-grade reference material for laboratory research.

Where it comes from

NAD+ (nicotinamide adenine dinucleotide) has one of the longest pedigrees in biochemistry. It was first glimpsed in 1906, when Arthur Harden and William Young found that a small, heat-stable factor in yeast extract was needed to keep fermentation going -- they called it a 'coferment.' Over the following decades Hans von Euler-Chelpin worked out its structure and Otto Warburg showed it shuttles hydrogen and electrons in metabolism. We now know it as a coenzyme the body builds from vitamin B3, sitting at the center of how cells turn food into energy.

What it does — in plain terms

NAD+ works like a rechargeable battery your cells pass around to get chemical work done, especially turning food into usable energy. Levels naturally decline as we age, which is why it's a huge topic in aging research. Labs study how NAD+ powers energy production, helps repair DNA, and switches on a family of 'maintenance' proteins called sirtuins that are linked to healthy aging.

How it works

NAD+ works in two very different ways, and that dual life is what makes it so central. Its classic job is as an electron shuttle: NAD+ picks up electrons and hydrogen (becoming NADH) as fuel molecules are broken down, then drops them off at the mitochondria to drive ATP production. Cells cycle between NAD+ and NADH constantly -- think of it as a rechargeable carrier the cell passes around to get chemical work done.

The second role is as a consumable signal. A family of enzymes actually cleaves NAD+ to do their work: sirtuins (linked to metabolism and aging), PARPs (which help repair damaged DNA), and others such as CD38. Because these enzymes use NAD+ up, the cell's NAD+ level becomes a kind of readout of its metabolic and stress state -- which is why so much research connects NAD+ availability to DNA repair and to the 'maintenance' proteins called sirtuins.

The thread tying the field together is that NAD+ levels tend to decline with age. That observation has driven intense interest in whether restoring NAD+ -- often using precursors such as NMN or NR that cells convert into NAD+ -- can influence metabolism and age-related decline in study models. This is an active and still-unsettled area of research.

What the research shows

NAD+ is unusual among research molecules in that its core biochemistry is rock-solid and textbook, while the headline-grabbing claims -- that boosting NAD+ can slow aging -- are far less settled. The mechanistic and review literature below is strong on how NAD+ works; the human evidence, largely from early trials of precursors like NMN, mostly speaks to safety rather than proven anti-aging benefit. That distinction matters when reading the studies.

• Endocrine Reviews, 2023 — reviewed NAD+ biology in aging, summarizing how declining NAD+ is linked to age-related metabolic and cellular changes.
• Cells, 2024 — examined NAD+ in models of skin aging, exploring its effects on skin-cell function and oxidative stress.
• Trends in Cell Biology, 2014 — described how NAD+ availability controls sirtuin activity, tying the coenzyme to the regulation of aging-related pathways.
• Science, 2015 — surveyed NAD+'s central roles in metabolism, DNA repair, and neurodegeneration, and the rationale for restoring NAD+ in aging.
• Advances in Nutrition, 2023 — reviewed human clinical trials of the NAD+ precursor NMN, reporting it was generally well tolerated while anti-aging benefits remained unproven.
• Nature Cancer, 2025 — linked falling NAD+ levels to impaired function of CAR-T (engineered immune) cells in laboratory studies.
• Nature Reviews Molecular Cell Biology, 2021 — detailed how NAD+ metabolism shifts during cellular ageing and how those changes affect energy production and DNA repair.
• Journal of Advanced Research, 2022 — evaluated NMN as an anti-aging product, weighing its proposed benefits against gaps in safety and efficacy data.
• Aging Cell, 2024 — examined the links between NAD+ metabolism, cellular senescence, and aging.
• Antioxidants & Redox Signaling, 2023 — reviewed NAD+ signaling in neurological disorders, discussing its role in neuronal energy metabolism and stress resilience.

What NAD+ is studied for

Cellular energy production. NAD+/NADH cycling is a backbone of metabolism, carrying the electrons that ultimately drive ATP synthesis. This is the most established part of NAD+ biology.

DNA repair. PARP enzymes consume NAD+ as they help detect and repair DNA damage, which links the cell's NAD+ pool directly to genome maintenance.

Sirtuin activity. The sirtuin 'maintenance' proteins depend on NAD+ to function, so researchers study NAD+ as a lever on the pathways sirtuins regulate in metabolism and aging.

Aging and precursors (NMN/NR). Because NAD+ falls with age, much work asks whether precursors such as NMN and NR can raise it. Early human trials suggest these are generally well tolerated, but clear anti-aging benefit has not been established.

Storage & handling

NAD+ is a coenzyme rather than a peptide, but as a lyophilized powder it is handled similarly: kept cold and dark, refrigerated for short holds or frozen for longer storage, and protected from moisture since it is hygroscopic. Once reconstituted with bacteriostatic water it should be refrigerated at about 2-8 C, shielded from light, used promptly, and kept from repeated freeze-thaw cycles. See the reconstitution reference below for concentration details.

Reconstitution reference

Standard laboratory reconstitution volumes for NAD+, from the VNG Reconstitution Sheet. See the full reconstitution guide for the method and concentration math.