What is NAD⁺?
Nicotinamide adenine dinucleotide
NAD⁺ is a small helper molecule that every cell needs to turn food into energy and to power its repair crews.
Imagine a fleet of delivery vans that carry energy around inside your cells. NAD⁺ is the van. Without enough vans, food sits in the warehouse and never becomes usable energy. Some of the vans also deliver fuel to the cell's repair teams, which can't work without it.
Why it matters for aging
NAD⁺ does two big jobs. First, it shuttles energy inside the mitochondria, the cell's power plants, as food is turned into usable energy. Second, it is the fuel for enzymes that repair DNA and for sirtuins, proteins that help cells manage stress and maintenance.
In animal studies and some human tissues, NAD⁺ levels fall with age. That's why it became one of the most talked-about molecules in longevity: if levels drop, maybe topping them up slows some parts of aging. The human evidence for that last step is still thin, which is exactly why we grade it carefully.
A common myth
NAD⁺ drips and boosters reverse aging.
NAD⁺ precursors such as NR and NMN do raise NAD⁺ levels in human blood. But so far, trials in healthy people show small or no effects on how muscles, metabolism or aging actually work. Promising, not proven. IV drips have even less evidence behind them.
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Updated Nov 7, 2026 · All terms