Melatonin is a hormone your body naturally produces and is responsible for regulating your sleep cycle and counterbalancing the stress hormone cortisol. Melatonin has just recently been applied topically for skin benefits, but research shows that it may be a more potent antioxidant than Vitamin C or E for its ability to penetrate cellular membranes and protect mitochondria and DNA from oxidative damage. It also stimulates your body to produce more antioxidant enzymes, resulting in additional healing from oxidative stressors such as UV light, blue light and pollution.