Cholesterol-like molecules found in all plant foods; the highest concentrations are found in vegetable oils. Phytosterols in the natural diet may lower cholesterol (Sources: Annual Reviews of Nutrition, 2002, volume 22, pages 533–549; and Metabolism, May 2002, pages 652–656). However, regarding topical application, there is research showing that the high lipid content of phytosterols can make the skin extremely sensitive to light (Source: Photochemistry and Photobiology, September 1997, pages 316–325).