What Is It? In the late 1980s, scientists realized that alpha-lipoic acid, a compound initially classified as a vitamin when it was discovered three decades earlier, possessed potent antioxidant properties that could prevent healthy cells from getting damaged by unstable oxygen molecules called free radicals. In fact, this vitaminlike compound has proved to be many times more potent than such old guard antioxidants as vitamins C and E. As a perk, it even recycles C and E (as well as other antioxidants), enhancing their effectiveness. Because it dissolves in both water and fat, this so-called "universal antioxidant" is able to scavenge more wayward free-radical cells than most antioxidants, the majority of which tend to dissolve in either fat or water but not both. Alpha-lipoic acid can reach tissues composed mainly of fat, such as the nervous system, as well as those made mainly of water, such as the heart. Health Benefits In addition to functioning as an antioxidant, this hard-working nutrient assists the B vitamins in producing energy from the proteins, carbohydrates, and fats consumed through foods. Intravenous forms of alpha-lipoic acid are administered in hospitals to treat cases of acute mushroom poisoning and for other cases of acute poisoning that affect the liver. Studies indicate that alpha-lipoic acid supplements hold promise for treating various disorders, including HIV infection, liver ailments, and glaucoma. But it has been most intensively studied for preventing complications from diabetes.