Naturally-occurring, cholesterol-like molecules found in all plant foods; the highest concentrations are found in vegetable oils such as canola, peanut, safflower, and sesame. Overall, though, nuts, seeds, and legumes are excellent sources of phytosterols, both for the body and for skin. Applied to skin, research has shown that phytosterols can stop the formation of substances in skin that break down collagen. These substances are more prevalent in sun-damaged skin, so phytosterols can be a good addition to skincare when the goal is reducing signs of sun damage. Soy phytosterols can help repair a damaged skin barrier, while a common type of phytosterol known as beta-sitosterol has been shown to reduce symptoms of atopic dermatitis (Sources: Experimental Biology and Medicine, April 2014, pages 454-464; Der Hautarzt, July 2008, pages 557-562; Journal of Cosmetic Science, May-June 2008, pages 217-224; Bioresource Technology, September 2007, pages 2,335-2,350).