If you have been following the longevity field for even just a little a while, you have probably heard of NAD+… a lot. So what is NAD+, and why are people excited about it? — The Importance of NAD+ in Cellular Health Nicotinamide adenine dinucleotide or NAD+ is essential for the fundamental biological processes of cellular health like energy production, metabolism, DNA repair, mitochondrial function, and more. NAD+ is vital for glycolysis, the citric acid cycle, and the electron transport chain, which is how the cells produce their energy. …