Niacinamide (5%)
Niacinamide, also known as vitamin B3 or nicotinamide, is a water-soluble vitamin produced synthetically for cosmetic use. It is odorless, comes in white powder form, and carries CAS # 98-92-0. It is a multi-functional ingredient with a broad range of studied skin benefits including anti-aging, skin brightening, barrier repair, and anti-acne activity. Studies typically use concentrations of 2–5% for various benefits, with anti-aging studies commonly using 4–5% daily for 8–12 weeks.
Niacinamide boosts collagen and key structural protein production (keratin, filaggrin, involucrin), reducing wrinkles and improving skin structure. At 2–5% it significantly fades 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 demonstrates sebum-regulating and anti-inflammatory properties useful for acne, rosacea, and atopic dermatitis.
No specific cautions or 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 it works via a different mechanism than those ingredients.
