MAPT and Alzheimer disease: Restoring brain NAD+ concentration using the dietary NAD+ precursor nicotinamide riboside (NR) has shown strong efficacy in animal models and has improved key features of neurodegenerative disorders, including amyloid‐beta (Aβ) and tau pathologies (hallmarks of Alzheimer's disease (AD)), neuroinflammation, and mitochondrial dysfunction (Hou et al., 2021; Schöndorf et al., 2018; Xie et al., 2019).