5-Amino-1-methylquinolinium (5-Amino-1MQ) is a potent small-molecule inhibitor of nicotinamide N-methyltransferase (NNMT), an enzyme implicated in metabolic dysfunction and adipogenesis. By suppressing NNMT activity, 5-Amino-1MQ helps restore cellular NAD+ availability and supports healthy mitochondrial energy metabolism. Research suggests it may play a role in reducing fat cell differentiation, improving insulin sensitivity, and promoting favorable changes in body composition — making it of significant interest in metabolic and longevity research.