NAD+ (Nicotinamide Adenine Dinucleotide)

NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell, where it serves as a fundamental mediator of energy metabolism, DNA repair, and cellular signaling. NAD+ levels decline dramatically with age — by roughly 50% between early adulthood and midlife — and this decline is implicated in many hallmarks of cellular aging. In skincare, NAD+ precursors and supporting molecules represent the frontier of longevity-focused formulation, targeting skin aging at its cellular roots rather than its visible surface symptoms.

How It Works

NAD+ functions as a coenzyme for hundreds of enzymatic reactions central to skin health. In energy metabolism: NAD+ enables the mitochondrial electron transport chain, which generates ATP — the cellular energy currency. Depleted NAD+ means less cellular energy for repair, synthesis of structural proteins, and maintenance processes. In DNA repair: NAD+ is consumed by PARP enzymes (poly-ADP ribose polymerases) that repair UV-damaged and oxidatively damaged DNA. As NAD+ declines, DNA damage accumulates unchecked. In longevity signaling: sirtuins, a family of proteins implicated in longevity and cellular stress resistance, require NAD+ as a substrate — depleted NAD+ impairs sirtuin activity and reduces the skin's ability to cope with stressors. In topical skincare, direct NAD+ penetration is limited by the molecule's size; products therefore typically use NAD+ precursors (niacinamide, NMN, NR) or supporting cofactors that the cell can convert to NAD+.

What the Research Shows

The scientific evidence for NAD+ in skin longevity draws from multiple research streams. Population-scale studies confirm that skin NAD+ levels decline with age and correlate with reduced mitochondrial function and impaired UV damage repair. Cell culture and animal studies demonstrate that boosting NAD+ via precursors like NMN improves mitochondrial function, reduces senescent cell burden, and enhances repair capacity. In human clinical contexts, niacinamide — the most established NAD+ precursor — has demonstrated SPF-independent photoprotection: a study in Carcinogenesis showed that topical 5% niacinamide reduced UV-induced DNA damage markers in skin by approximately 25% versus vehicle. Direct topical NAD+ and NMN supplementation in skincare is a newer field; early controlled studies show improvements in skin texture, hydration, and barrier function, but the evidence base is not yet as mature as for niacinamide specifically.

How To Use It

NAD+ precursor serums and creams are typically applied morning and/or evening after cleansing. Since niacinamide is the most established and cost-effective NAD+ precursor, a quality niacinamide serum is a practical starting point. More advanced longevity formulations use NMN (nicotinamide mononucleotide) or NR (nicotinamide riboside) at higher molecular weights than niacinamide — apply these serums before moisturizer. Pair with broad-spectrum SPF 50+ for maximum DNA damage prevention, as UV radiation is the largest driver of NAD+ depletion in skin.