Authors’ contributions
MM
MI, MM, TK, and TY designed the NMN-supplementation trial and MI, TY, YF, TSato and TSakurai provided resource for the study. YNN, MI, and MM conducted the clinical trials. YNN conceptualized this sub-analysis study. KY and TN performed the analysis of NAD+-related metabolites. YNN and KK conducted statistical analyses. YNN, MI, and TY interpreted the data. YNN wrote an original draft. YNN, MI, and KK, prepared figures and tables. YNN, MI, KK, and TY reviewed and edited. MI, TK and TY supervised. All authors have read and agreed to the published version of the manuscript.