NAD+ (nicotinamide adenine dinucleotide) is a crucial coenzyme found in all living cells, playing a vital role in numerous cellular processes. It's essential for energy production, DNA repair, and cell survival. NAD+ levels naturally decline with age, and this decline is linked to age-related diseases. Restoring NAD+ levels through supplementation or other means is being explored as a potential way to combat these age-related declines and improve overall health and longevity.