Alpha lipoic acid is a fatty acid found naturally inside every cell in the body. It's needed by the body to produce the energy for our body's normal functions. Alpha lipoic acid converts glucose (blood sugar) into energy. Alpha lipoic acid is also an antioxidant, a substance that neutralizes potentially harmful chemicals called free radicals. What makes alpha lipoic acid unique is that it functions in water and fat, unlike the more common antioxidants vitamins C and E, and it appears to be able to recycle antioxidants such as vitamin C and glutathione after they have been used up. Glutathione is an important antioxidant that helps the body eliminate potentially harmful substances. Alpha lipoic acid increases the formation of glutathione. Alpha lipoic acid is made by the body and can be found in very small amounts in foods such as spinach, broccoli, peas, Brewer's yeast, brussel sprouts, rice bran, and organ meats. Alpha lipoic acid supplements are available in capsule form at health food stores, some drugstores, and online. For maximum absorption, the supplements should be taken on an empty stomach.