https://www.nature.com/articles/s42255-020-0197-6Maintaining cellular NAD levels through supplementation with intermediates of NAD synthesis has considerable health benefits. A new study demonstrates that the reduced form of nicotinamide riboside, NRH, can be converted to NAD in a biosynthetic pathway that involves adenosine kinase, thus strongly boosting NAD levels in cells and tissues.
https://www.nature.com/articles/s42255-020-0194-9.pdf