By middle age, our NAD+ levels have plummeted to half that of our youth. Numerous studies have demonstrated that boosting NAD+ levels increases insulin sensitivity, reverses mitochondrial dysfunction, and extends lifespan. NAD+ levels can be increased by activating enzymes that stimulate synthesis of NAD+, by inhibiting an enzyme (CD38) that degrades NAD+, and by supplementing with NAD precursors, including nicotinamide riboside(NR) and nicotinamide mononucleotide (NMN)...Here, we look at the science behind NMN, its stability, possible pharmacokinetics, transport, function, and ability to induce biosynthesis of NAD+. Supplementing NMN may be an effective nutraceutical anti-aging intervention, with beneficial effects on a wide array of physiological functions.