NAD+ is an essential coenzyme in cellular life processes, playing central roles in energy metabolism, DNA repair and anti-aging, cellular stress response and signal regulation, as well as neuroprotection. In energy metabolism, NAD+ functions as a key electron carrier in glycolysis, the tricarboxylic acid cycle, and mitochondrial oxidative phosphorylation, driving ATP synthesis and supplying energy for cellular activities.

At the same time, NAD+ serves as a crucial substrate for DNA repair enzymes and activator of sirtuins, thereby maintaining genomic stability and contributing to longevity. Under conditions of oxidative stress and inflammation, NAD+ participates in signaling pathways and calcium regulation to preserve cellular homeostasis. In the nervous system, NAD+ supports mitochondrial function, reduces oxidative damage, and helps delay the onset and progression of neurodegenerative diseases. Since NAD+ levels naturally decline with age, strategies to maintain or enhance NAD+ are increasingly recognized as important for promoting health and slowing aging.