Niacinamide is a water-soluble form of vitamin B3 that supports the skin barrier, helps balance visible oil, and fades the look of post-blemish marks over time. It is one of the most studied cosmetics ingredients at everyday concentrations of 2–5%.
Peer-reviewed dermatology literature links niacinamide to improved barrier function and reduced transepidermal water loss; in Coyglow's Barrier Repair Serum it anchors a 3:1:1 ceramide partnership.
How to use: Morning or evening, after cleansing and before heavier creams. Pairs well with almost everything — retinal, vitamin C, and acids included.
Cautions: Well tolerated by most skin types, including sensitive skin.