Nicotinamide mononucleotide (NMN) is a nucleotide derived from ribose and nicotinamide, serving as a crucial precursor in the biosynthesis of nicotinamide adenine dinucleotide (NAD+), a vital coenzyme in cellular metabolism. Researchers primarily study NMN for its potential role in enhancing metabolic health and mitigating age-related physiological decline. Key findings from recent studies indicate that NMN supplementation can improve insulin sensitivity and metabolic function in prediabetic populations, as well as alleviate age-associated physiological decline in animal models by enhancing mitochondrial function and energy metabolism. Current research continues to explore NMN's effects on various biological processes, including its implications for aging and immune function, highlighting its potential as a significant area of investigation in metabolic and age-related disorders.