NADIA means NAD+ In Action. Nicotinamide Adenine Dinucleotide (NAD) is a coenzyme found in all living cells. It is responsible for DNA repair, and it works with proteins to provide cellular nutrition and to preserve cellular health. NAD+ levels decline with age, and diminishing levels cause visible signs of aging to become evident. NADIA skincare delivers highly concentrated NAD+ to the skin and incorporates all of the ingredients you have come to expect from high-performance treatment products.