NAD+ is essential for cellular functions and energy production. It acts as a carrier for electrons in the mitochondrial respiration process, where it helps convert nutrients into ATP (adenosine triphosphate), the energy currency of our cells. However, as we age, NAD+ levels naturally decline, which has been linked to various age-related disorders and decreased metabolic efficiency. This decline can result in a host of issues, including decreased energy levels, increased fatigue, and a general decline in physical and cognitive functions.