Beard oil helps men nourish the skin underneath their beard, as well as the hair follicles themselves. It is intended to mimic the natural oils that the skin produces, keeping the beard looking soft, shiny, and smooth. Components like sebum are needed to keep your beard looking thicker and fuller by maintaining hairs natural oil composition. Without the proper levels of moisture in your skin and hair, your beard may become flaky, thinner, and less likely to grow.