Skin is the largest human organ; however, this vital organ is constantly exposed to the environment – air, ultraviolet light, pollution, and weather to name a few. Skin damage is due to several factors, including stress, poor diet, environmental pollution, and exposure to ultraviolet radiation. It is estimated that among all these environmental factors, ultraviolet radiation contributes up to 80% of extrinsic damage to skin. Likewise, free radical or reactive oxygen species (ROS) development is ultraviolet-induced, compounding pollutant damage and causes extreme oxidative stress on skin.1 Free radicals and skin aging influence other processes, such as advanced glycation end products (AGE) and strategies for protecting skin against them and signs of aging. Want to read more? Subscribe to continue reading this article, plus gain access to all DERMASCOPE has to offer. SUBSCRIBE Lydia Sarfati is an international industry leader, with over 46 years of experience as a spa owner, consultant, and aesthetician. She is the founder and CEO of Repêchage, the first company to bring seaweed-based skin care treatments to the United States market and is the President of CIDESCO Section U.S.A, the world's major international beauty therapy association. She appears at industry tradeshows, is the author of “Success at Your Fingertips: How to Succeed in the Skin Care Business,” and “The Repêchage Book of Skincare Science & Protocols,” and is a contributing author to textbooks, such as “The Milady Standard Esthetics: Fundamentals, Twelfth Edition, and Oncology Esthetics.” Want to read more? Subscribe to one of our monthly plans to continue reading this article.