Alpha lipoic acid (LA) is an important micronutrient in humans. Its role as vitamin is questionable but it is a vitamin like antioxidant that body produces naturally. It is an important cofactor of multiple enzymes, most of them are important in citric acid cycle and glycine cleavage system. LA is also a natural chelating agent and can bind to certain transitional elements such as iron and copper and certain heavy metals. LA may have beneficial role in improving vision and neuropathy in diabetes.