The skin possesses an elaborate antioxidant defense system to deal with this stress. However, excessive exposure to UV light can overwhelm the skin's antioxidant capacity, leading to oxidative damage and ultimately to skin cancer, and premature skin aging. Several studies have shown that people with a variety of sun-related skin disorders have lower levels of antioxidants. Indeed, in some patients with melanoma an imbalance of the antioxidant system has been identified. Replenishing the skin's antioxidant capabilities is one way to decrease the risk of skin cancer.
Studies are mixed about the benefit of individual antioxidants.
Indeed, in some studies, it was found that too much of a single antioxidant could even have damaging effects. However, there are clear benefits to some antioxidants, and the most promising results were obtained in studies combining several compounds, often resulting in synergism of the protective effects. It also is believed to be a key factor in minimizing light induced damage to the eye. It has been shown to reduce the ability to reduce skin cancers in mice. It may work topically as well as orally.