Lipoic acid, also known as alpha-lipoic acid, is a sulfur-containing fatty acid. It is found inside every cell of the body, where it helps generate the energy that keeps us alive and functioning. Lipoic acid is a key part of the metabolic machinery that turns glucose (blood sugar) into energy for the body's needs.
It is thought that certain nerve diseases are at least partially caused by free radical damage. Thanks to its combined fat and water solubility, lipoic acid can get into all the parts of a nerve cell and potentially protect it against such damage. This is the rationale for studies on the potential benefits of lipoic acid for diabetic neuropathy.
Liver and yeast contain some lipoic acid. Nonetheless, supplements are necessary to obtain therapeutic dosages.
The typical dosage of oral lipoic acid for treating complications of diabetes is 100 to 200 mg 3 times daily. In studies that found benefits, several weeks of treatment were often necessary for full effects to develop.
For use as a general antioxidant, a lower dosage of 20 to 50 mg daily is commonly recommended, although there is no evidence that taking lipoic acid in this way offers any health benefit.
What Is the Scientific Evidence for Lipoic Acid?
Diabetic Peripheral Neuropathy
There is some evidence that intravenous lipoic acid can reduce symptoms of diabetic peripheral neuropathy, at least in the short term. However, the evidence for oral lipoic acid remains weak and contradictory.
However, while this outcome may sound promising, one feature of the results tends to reduce the faith one can put in them: the absence of a dose-related effect. Ordinarily, when a treatment is effective, higher doses produce relatively better results. When such a spectrum of outcomes is not observed, one wonders if something went wrong in the study.
Diabetic Autonomic Neuropathy
There is better evidence for oral lipoic acid in a form of diabetic neuropathy affecting the nerves that supply the heart: autonomic neuropathy.
Burning Mouth Syndrome
Individuals with burning mouth syndrome (BMS) feel chronic scalding pain in the mouth, as if they had consumed an excessively hot drink. Although the cause of BMS is not known, the symptoms resemble those of neuropathy, and for that reason, researchers have investigated the potential benefits of lipoic acid.
Safety for young children, women who are pregnant or nursing, or those with severe liver or kidney disease has not been established.
- Reviewer: EBSCO CAM Review Board
- Review Date: 07/2012 -
- Update Date: 07/25/2012 -