Nicotinamide

Abstract Nicotinamide (vitamin B3, Niacinamide) is a water-soluble NAD⁺/NADP⁺ precursor central to epidermal energy metabolism and cutaneous homeostasis. As an ingestible nutricosmetic, a 10 mg/day dose (~66% U.S. DV) provides a functionally active yet well-tolerated intake that supports multiple skin targets. Mechanistically, nicotinamide upregulates barrier lipids (ceramides, free fatty acids, cholesterol), boosts natural moisturizing factors via filaggrin pathways, inhibits melanosome transfer to even tone, and enhances repair of UV-induced DNA damage while reducing oxidative stress - together improving resilience, hydration, and brightness with high tolerability. Clinically, low-dose ranges (~8-20 mg/day) are associated with improvements in dryness/sensitivity, TEWL, and dyschromia, without flushing seen with nicotinic acid. In multi-ingredient systems, nicotinamide shows strong formulation synergy: with Ceramide NP for dual-tier barrier restoration, hyaluronic acid for layered hydration, elastin peptides for elasticity under oxidative control, and vitamin C for complementary brightening/antioxidant effects. These properties position oral nicotinamide 10 mg as a mechanistically coherent, safe, and evidence-based cornerstone for beauty-from-within strategies targeting barrier repair, hydration maintenance, tone uniformity, and photo-environmental defense.