Haakon Berven, Magnus Svensen, Heidi Eikeland, Nora Tvedten, Erika Sheard, Solveig Amdahl Af Geijerstam, Mona Søgnen, Adrian McCann, Lena Arnsten, Ove Arseth, Vivian Skjeie, Arve Hjellbrekke, Geir-Olve Skeie, Yamila N. Torres Cleuren, Gonzalo S. Nido, Kristoffer Haugarvoll, Frank Riemer, Charalampos Tzoulis, Christian Dölle
= 6) receiving 1,200 mg/day nicotinamide riboside or nicotinamide mononucleotide. Blood NAD increased slowly, plateauing after approximately two weeks of treatment, and declined with similarly slow kinetics following treatment discontinuation. Cerebral NAD levels increased measurably after four weeks of treatment. NAD-related metabolites showed faster increase and washout dynamics compared to NAD itself. Collectively, these data suggest that effective NAD-AT requires sustained oral administration over at least 2-4 weeks and that once-daily dosing is sufficient to maintain stable NAD levels. NAD responses exhibited considerable interindividual variability, but were not influenced by disease status or sex, indicating broad applicability.