NAD⁺ (nicotinamide adenine dinucleotide) is a coenzyme found naturally in every cell of the body. It plays an important role in cellular energy metabolism and is involved in numerous processes that help our cells function and maintain themselves.NAD⁺ has become an important area of longevity research because NAD⁺ metabolism can change as we age. Understanding how to support healthy cellular function is therefore central to the science of intelligent ageing.