Emollients keep water already present in the skin from being lost into the air. As a result, they act as a moisturizer. Emollients also soften and smooth the skin through their effects. Emollients are in almost all moisturizing products. They vary in viscosity (i.e., thickness) and effectiveness. While they are more effective as a moisturizer, thick, greasy emollients are generally not well-tolerated for long-term daily use on the entire face.

One of the most used and effective emollients is petrolatum. It is found in products such as Aquaphor©, Vaseline©, ChapStick©, and many others. However, petrolatum is thick (i.e., viscous) and greasy. Products like Aquaphor© and Vaseline© that contain a large amount of petrolatum may be good options to apply to incisions after surgery and during the early stages of healing because moisture encourages healing. Another benefit is that petrolatum is non-allergenic.

Another example of an emollient is dimethicone, which is derived from silicon. Dimethicone is found in many moisturizers because it is thinner and, therefore, less likely to feel greasy. Silicon-based emollients like dimethicone are major ingredients in scar gels, which are typically used for months on surgical incisions to improve healing. They are, however, less effective emollients than petrolatum. It is for that reason that petrolatum-containing products are often used early in incision healing and silicon-based scar gels are used later and longer-term.

Some plant-based oils, such as olive oil, can also function as emollients. One component of olive oil, squalene, is found in many moisturizers. The hydrogenated version of squalene, called squalane, is more stable than squalene and less comedogenic (less likely to clog pores). Squalane is used instead of olive oil because olive oil contains other compounds, such as oleic acid, that may damage the skin barrier.