NAD+: Where the Science Is Solid and Where the Delivery Argument Falls Apart

The underlying biology is not in dispute

NAD+ is a coenzyme central to redox reactions and to sirtuin and PARP activity. Around 210 studies in our index touch it. What is contested is whether administering NAD+ directly is the best way to raise cellular levels.

The precursor argument

Much of the human research investment has gone into precursors such as NR and NMN rather than NAD+ itself, on the basis that the intact molecule is poorly taken up by cells.

Vendors rarely acknowledge this debate. We grade the evidence Emerging for that reason: strong background science, unsettled delivery question.

Stability and handling

NAD+ degrades faster than most compounds in this index, particularly in solution and at room temperature. Cold-chain claims and reconstitution guidance are more meaningful signals here than elsewhere.

Pricing

500mg vials typically run £39 to £62. Per-milligram cost is low, but shipping and storage requirements affect real cost more than the sticker price does.