NAD+

NAD+ is a coenzyme, not a peptide, that every cell uses to shuttle electrons during energy production and that two key enzyme families (sirtuins and PARP DNA-repair enzymes) require as a substrate to function. Tissue NAD+ levels decline measurably with age, which is the basis for interest in raising it. Most human clinical research on raising NAD+ has studied oral precursors (NMN, NR), not the injectable vial product sold here — see our full research writeup for the human trial data. Injectable/subcutaneous NAD+ has essentially no published human dosing research; what follows is sourced from clinical and compounding practice, not clinical trials.