Across the kingdom of life, an increase in intracellular levels of NAD+ triggers shifts that enhance survival, including boosting energy production and upregulating cellular repair.¹ In fact, the slow, ineluctable process of aging has been described as a “cascade of robustness breakdown triggered by a decrease in systemic NAD+ biosynthesis and the resultant functional defects in susceptible organs and tissues.”² Aging is marked by epigenetic shifts, genomic instability, altered nutrient sensing ability, telomere attrition, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and dysregulated intercellular communication.^3,4

By middle age, our NAD+ levels have plummeted to half that of our youth.⁵ Numerous studies have demonstrated that boosting NAD+ levels increases insulin sensitivity, reverses mitochondrial dysfunction, and extends lifespan.^6,7 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).^8,9 A conceptual framework called NAD World, formulated over the last decade by developmental biologist Shin-ichiro Imai, MD, PhD, of Washington University School of Medicine, posits NMN as a critical, systemic signaling molecule that maintains biological robustness of the communication network supporting NAD+.²

Taken orally, NMN is rapidly absorbed and converted to NAD+.¹⁰ In numerous studies, supplementation with NMN has increased NAD+ biosynthesis, suppressed age-related adipose tissue inflammation, enhanced insulin secretion and insulin action, improved mitochondrial function, improved neuronal function in the brain, and more. Here, we look at the science behind NMN, its stability, possible pharmacokinetics, transport, function, and ability to induce biosynthesis of NAD+.¹¹ Supplementing NMN may be an effective nutraceutical anti-aging intervention, with beneficial effects on a wide array of physiological functions.¹²