Emollient plant oil similar in benefits to several other non-fragrant plant oils. The concept of olive oil having anti-aging properties stems from some evidence that diets high in olive oil may help prevent heart disease. Olive oil is beneficial for dry skin because of its fatty acid content, some of which comes from the emollient squalene. Olive oil contains essential fatty acids dry skin needs, including oleic, palmitic, and linoleic acids. It also contains phenolic compounds that provide antioxidant benefit. There are also a small number of animal tests showing that topically applied olive oil can protect against UVB damage (Sources: Talanta, December 2009, pages 924-934; International Journal for Vitamin and Nutrition Research, May 2009, pages 152–165; Molecules, January 2009, pages 540–554; Annals of Internal Medicine, September 2006, pages 333–341; European Journal of Clinical Nutrition, January 2002, pages 72–81; and Lipids, November 2001, pages 1195–1202, and Supplemental, pages S49–S52; Carcinogenesis, November 2000, pages 2085–2090; and Journal of Dermatological Science, March 2000, Supplemental, pages S45–S50).
Interestingly, olive oil used alone has been shown to be somewhat problematic for skin because, used alone, it seems to reduce skin's barrier integrity and delay healing of injured skin, especially when compared to sunflower seed oil, a plant oil whose fatty acid profile is markedly different from olive oil. It is believed that olive oil's high oleic acid content may be responsible for this, but this plant oil maintains a low potential for irritancy or allergic reaction (Source: Pediatric Dermatology, January-February 2013, pages 42-50; Dermatitis, November-December 2008, pages 308-315; and Contact Dermatitis, January 1997, pages 5-10).
Just to be very clear: when olive oil is mixed in a formula in small amounts with other beneficial ingredients, you’re getting the benefit of its slip and emollient properties along with some antioxidant benefit. The downside to olive oil is when it's used alone on skin, particularly infant skin.