Niacinamide
Niacinamide, also known as vitamin B3 or nicotinamide, is a water-soluble vitamin that appears as a white powder and is odorless with a salty, bitter taste. It is found naturally in meat, fish, wheat, and small amounts in vegetables, but the cosmetic-grade version is produced exclusively synthetically. It is a multi-functional ingredient with a broad range of studied skin benefits, typically used at concentrations of 2–10% in topical formulations. Its CAS number is 98-92-0.
Niacinamide at 4–5% has demonstrated anti-aging and wrinkle-smoothing effects by boosting collagen and key structural protein production. At 2–5%, it significantly lightens hyperpigmentation by suppressing melanosome transfer, and at 2% it increases ceramide, free fatty acid, and cholesterol synthesis to strengthen the skin barrier and improve hydration. It also exhibits sebum-regulating and anti-inflammatory properties that benefit acne, rosacea, and atopic dermatitis.
No specific contraindications are noted in the source. The source does mention it can be combined with tyrosinase inhibitors (e.g., vitamin C, arbutin, kojic acid) for enhanced brightening effects, and that anti-aging benefits require consistent use at 4–5% for 8–12 weeks.
