According to our experts, the vitamin C type will also determine its effectiveness. Pure vitamin C, known as L ascorbic acid, ...

Despite its efficacy, vitamin C is notoriously unstable and can quickly go from a hyperpigmentation-zapping wonder ingredient to a $60 bottle of smelly serum ... as a young beauty editor, as ...

Instead, choose a vitamin C serum with only one of these ingredients alongside hydrating or soothing supporting ingredients. Irene Richardson is a beauty and fashion writer for the InStyle ...