%20is%20a%20vitamin%20that%20helps%20produce%20NAD+,%20a%20key%20molecule%20for%20metabolism.%20Although%20reports%20of%20negative%20effects%20from%20high%20doses%20of%20NR%20are%20rare,%20this%20study%20examined%20ho...){kind=link}
Effects of High-Dose Nicotinamide Riboside on White Fat Tissue Function and Insulin Sensitivity: Preclinical Findings
Synopsis
Nicotinamide riboside (NR) is a vitamin that helps produce NAD+, a key molecule for metabolism. Although reports of negative effects from high doses of NR are rare, this study examined how high-dose NR affects metabolism in male mice fed a mildly high-fat diet for 18 weeks. Mice given a high NR diet (9000 mg/kg) showed reduced metabolic flexibility, slower glucose clearance, and increased insulin resistance compared to those on a normal NR diet. These metabolic problems were linked to dysfunction in white fat tissue, including lower activity of SIRT1 causing reduced PPARγ function, weaker AKT/GLUT4 signaling important for glucose uptake, and increased inflammation with more macrophages and crown-like structures. Overall, high doses of NR caused white fat tissue dysfunction, which may partly explain the decline in metabolic health in these mice.
Journal
Nutrients