Translations:Nicotinamide riboside/6/en

The identification of Nicotinamide riboside (NR) as an NAD precursor in eukaryotes developed out of the study of pellagra. Pellagra was the first disease to be associated with NAD+ deficiency. It was linked to nutritional deficiency by Joseph Goldberger in 1914, and to deficiency of niacin (vitamin B₃) by Conrad Elvehjem in 1937. NAD+ (then called coenzyme I) was shown to be extremely low in cases of pellagra, and NA and NAM were identified as molecular precursors in rebuilding NAD+ levels. Pellagra is now understood as a severe, chronic depletion of NAD+, which can be treated through diet.