Alpha Lipoic Acid

Author: Allen S. Josephs, M.D., Jefferson Medical College, Board Certified in Internal Medicine & Board Certified in Neurology, Section Chief, Neurology, St. Barnabas Hospital, Livingston, NJ

A little known but extremely powerful antioxidant nutrient is available in supplemental form called alpha lipoic acid. It is a vitamin-like substance that contains sulfur. Alpha lipoic acid (ALA) plays an extremely important role in energy production within the cell. What makes alpha lipoic acid so effective as an anti-oxidant is that it works on both water and fat soluble free radicals which are the cause of oxidation.

For those of you who think that alpha lipoic acid (ALA) is a nutrient that has not been well researched, think again. A recent Medline search indicated 1,378 articles in the medical literature on alpha lipoic acid. Alpha lipoic acid appears to be a wonder nutrient. It seems to work particularly well in diabetic patients. Experimental studies show that it has a potential renal protective effect. In a study out of Germany published last year, diabetic patients treated with 600 mg of ALA daily had stabilization in urinary albumin concentration over an 18 month follow-up whereas patients in the control group had an increase in urinary albumin excretion. In animal studies the renal protective effects of ALA were not attributable to improved glycemic control alone but also likely related to its antioxidant activity. Alpha lipoic acid increases glucose uptake in the cells and appears to reduce symptoms of diabetic complications including cataract formation, vascular damage and even polyneuropathy (nerve damage). In a study published in the Journal Diabetic Medicine from 1999, those patients treated with 600 mg. of ALA, three times daily for 3 weeks had improvement of diabetic symptoms from polyneuropathy. In another study using 600 to 1,800 mg of ALA daily those individuals treated were found to have improvement of insulin sensitivity. In animal studies it has been found to reduce oxidative DNA damage within heart cells.

More recent experimental studies have shown that ALA can actually reverse the damage in aging cells of the brain. This was a study published in the prestigious journal Proceedings of the National Academy of Science from February of this year. In the study, aging rats were treated with either acetyl-L carnitine or ALA. Both of these nutrients improved performance in memory tasks by lowering oxidative damage and improving mitochondrial function. Electron microscopic studies of the brains of these animals indicated these nutrients reversed age associated mitochondrial structural decay.

Most studies have used 600-1,800 mg per day of alpha lipoic acid for optimal benefits in people with specific health concerns. If you are healthy and want to promote optimal health, a dose of 30 – 300 mg per day may be sufficient. Beware of products that contain 500 mcg (1/2 mg)-10 mg; these doses are probably too little to provide any benefit.

References:
Diabetes Res Clin Pract 2001 Jun;52(3):175-83
J Am Soc Nephrol 2002 Jan;13(1):108-16
Diabet Med 1999 Dec;16(12):1040-3
Free Radic Biol Med 1999 Aug;27(3-4):309-14
Free Radic Biol Med 1999 Nov;27(9-10):1114-21
FASEB J 2001 Mar;15(3):700-6
Proc Natl Acad Sci USA 2002 Feb 19;99(4):2356-61