What does NAD+ do in the body?

In cells, NAD+ sits at the center of energy metabolism. In mitochondria, NADH hands electrons to the electron transport chain, which drives ATP synthesis. NAD+ is also consumed by PARP enzymes that flag and repair DNA breaks, by sirtuins that switch on stress-response genes, and by CD38, an enzyme found on immune cells. All three compete for the same pool.

Levels fall with age in many tissues. Human skin samples showed lower NAD+ in older adults, and in mice, rising CD38 drove much of the decline. That’s why NAD+ is a standard readout in aging and metabolism research. This describes cell biology, not the effects of any product. See our research purposes only policy, then shop NAD+ online.