if so, where are the studies on niacins or
even nicotinamide riboside (the latter is kind of unrelated, but should yield some niacin in vivo)(P.S. blog post on NR in the works).
Even if you have no interest in changing your diet or exercise regimen, and only want to learn more about NAD + and perhaps take a NAD booster supplement like
Nicotinamide Riboside (NR) or
Nicotinamide Mononucleotide (NMN), you still need to read this page to better understand how critical it is to get your NAD + up.