NAD+ (Nicotinamide Adenine Dinucleotide) is a crucial coenzyme naturally present in every living cell, playing a vital role in various biological processes, particularly cellular metabolism, energy production, DNA repair, and maintaining overall cellular health. As a key player in energy metabolism, NAD+ supports mitochondrial function by facilitating ATP production, the primary energy source of cells. Additionally, NAD+ is essential for activating sirtuins—enzymes involved in cellular aging, longevity, and metabolic regulation—and aiding in the effective repair of DNA damage through its role as a substrate for PARP enzymes, which are crucial for maintaining genomic stability. With aging, NAD+ levels decline naturally, contributing to diminished energy, impaired cellular repair mechanisms, and increased susceptibility to age-related diseases. Consequently, supplementation or boosting of NAD+ levels has garnered significant attention for its potential anti-aging effects, improved metabolic health, enhanced cognitive function, and overall longevity promotion. Research continues to explore NAD+'s therapeutic potential, investigating its ability to mitigate neurodegenerative conditions, manage metabolic disorders, improve cardiovascular health, and enhance general vitality. Given its fundamental role in cellular homeostasis and promising outcomes observed in clinical and preclinical studies, NAD+ remains an exciting and extensively studied molecule in anti-aging science, regenerative medicine, and metabolic health optimization.