What is NAD+ and what does it do in your body?

NAD+ is a small molecule found in every cell of your body that is indispensable for converting food into energy. In the mitochondria, the power plants of your cells, NAD+ acts as a kind of molecular relay baton that passes electrons along. Without NAD+, energy production grinds to a halt.

NAD+ is also the fuel for two types of proteins that keep your cells healthy. First, for enzymes that repair DNA damage: these consume NAD+ every time they seal a break in the DNA. Second, for sirtuins, proteins that help manage oxidative stress and keep the mitochondria active. When NAD+ becomes scarce, both systems perform worse.

As we age, the amount of NAD+ in your tissues declines. In rodents, this decline is associated with muscle weakness, cognitive deterioration and metabolic problems. In animal research, restoring NAD+ was able to slow some of those effects. Whether the same holds true in humans has not yet been convincingly demonstrated.

NAD+ also has an ambiguous role in inflammation. Immune cells consume large amounts of NAD+ when they spring into action, which is beneficial during an infection. In chronic intestinal inflammation, such as Crohn's disease, however, that same consumption drives the inflammation forward. NAD+ is therefore both essential for healthy cells and a fuel for inflammatory processes.

Finally, breakdown products of NAD+ influence the calcium balance in cells and, with it, whether a cell undergoes programmed cell death. And a special production route via the amino acid tryptophan yields substances that influence communication between brain cells, relevant to brain function and possibly psychiatric conditions.