Lipoic Acid 50 mg. Capsules Kirkman's Alpha-Lipoic Acid 50 mg. can be swallowed or mixed in food or beverage. The menthol flavor helps suppress the burning sensation lipoic acid often exhibits. Each capsule supplies alpha-Lipoic Acid 50 mg. Alpha-Lipoic Acid is a disulfide compound also known as thioctic acid. Lipoic Acid is a powerful and versatile antioxidant that helps protect the body against free radical damage and, as a result, is a protector of many types of cells and tissues. Lipoic Acid is a unique antioxidant in that it is both fat and water soluble. Other well known antioxidants can only function within their soluble media, such as vitamin E in fatty membranes of cells and vitamin C in watery portions of cells. Because of its dual solubility, lipoic acid can function in both fatty and aqueous phases of the cell. This is significant and makes lipoic acid a complete antioxidant capable of defending against a wide variety of invading free radicals. Alpha-Lipoic Acid has both sulfur atoms and carboxyl groups in its chemical structure, making it a very reactive compound. Alpha-Lipoic acid is converted into the reduced form, dihydrolipoic acid, inside of cells, and dihydrolipoic acid possesses two sulfhydryl groups. Alpha-Lipoic Acid is found naturally in foods such as spinach, broccoli, tomato, liver, heart and animal muscle tissue. Its bioavailability from food may be limited, however, because it is bound to a protein called "lipoyllysine". Preliminary research suggests that the lipoic acid found in supplements may be more biologically active that lipoic acid bound to this protein in food. It is important to use a high quality lipoic acid to get the desired effects. There is a lot of poor quality product imported into the United States which may not be pure or fully potent. Kirkman uses exclusively LIPOEC® brand manufactured by The Schroeder Group in Germany. In a comparison test of LIPOEC® against eight other manufacturers' lipoic acids, the LIPOEC® product surpassed all others in purity and exhibited a potency of 100%.