In recent years, scientists have come to understand the actual biochemical triggers that manifest skin aging, such as wrinkles, altered pigmentation, and loss of skin tone. These triggers are known as: • Reactive Oxygen Species (ROS), also known as free radicals. • Matrix Metalloproteinases (or MMPs). • Advanced Glycation End-products (AGEs).Reactive Oxygen Species (ROS) are dangerous oxygen molecules generated by UV rays and pollution. ROS attack and react with stable skin cell molecules, causing cross-linking of collagen and elastin (the cause of wrinkles) while lessening skin’s ability to repair itself.Matrix Metalloproteinases (MMPs) are enzymes activated by UV exposure or inflammation. MMPs contribute to the breakdown of collagen while inhibiting new collagen formation.The same glucose (sugar) that provides energy for our cells can also react with proteins, including the skin’s collagen. This reaction results in the formation of Advanced Glycation End-products (AGEs), which can contribute to loss of elasticity, wrinkles, inﬂammation, inhibited skin cell growth and accelerated aging.Because we understand these triggers, skin care professionals are better equipped to effectively treat, and control, the signs of skin aging.