When we hear "oily skin," we think of "blemishes," "enlarged pores," "shiny appearance," or "oily zones." These characteristics, which are not very flattering, give this skin type an impression of dirtiness and a bad reputation. This shine is largely due to the layer of sebum that covers the skin's surface. However, a number of substances claim to have the ability to reduce the amount of sebum, such as niacinamide. It could be a good option for those with oily skin tendencies. But what does the dermatological literature say?