Question: is nad and nadh the same?
Answer: NAD+ and NADH: Two Sides of the Same Coin. NAD can exist in two forms: NAD+ and NADH. These two forms of NAD are known as a "redox couple," a term that is used to describe a reduced (the "red" in redox) and oxidized (the "ox" in redox) form of the same atom or molecule.