Alpha-lipoic acid inhibits nerve damage, including diabetic neuropathy characteristic of diabetic patients.
Alpha-lipoic acid reduces insulin resistance and improves blood glucose balance in diabetic patients.
Alpha-lipoic acid protects the liver from poisoning by environmental toxins, such as industrial chemicals or toxic heavy metals, as well as being used (in injectible form) to save the lives of people who have mistakenly eaten poisonous mushrooms.
What is alpha-Lipoic acid?
Alpha-Lipoic acid (also known as thioctic acid) is a vitamin like substance which plays an important role in the bodys energy supply processes. Alpha-lipoic acid is also important within the body as a powerful antioxidant capable of protecting both the lipid (cell membrane) and aqueous (cytoplasmic) cellular compartments from free radical induced damage. Alpha-lipoic acid is mainly obtained from the diet, although small amounts are also manufactured within the body. Red meat (especially liver, spinach and brewers yeast are good sources of alpha-lipoic acid.
What does alpha-Lipoic acid do?
Alpha-lipoic acid works in conjunction with the B vitamins thiamin, riboflavin, niacin and pantothenic acid to convert sugars and fat into energy within the body. Alpha-lipoic acid, together with its active metabolite dihydrolipoic acid, are powerful antioxidants which uniquely are equally effective in protecting both the aqueous and lipid compartments of the cell from free radical damage.
Clinical studies have shown supplementation with alpha-lipoic acid to have the following benefits:
- Alpha-lipoic acid inhibits nerve damage, including diabetic neuropathy characteristic of diabetic patients.
- Alpha-lipoic acid reduces insulin resistance and improves blood glucose balance in diabetic patients.
- Alpha-lipoic acid protects the liver from poisoning by environmental toxins, such as industrial chemicals or toxic heavy metals, as well as being used (in injectible form) to save the lives of people who have mistakenly eaten poisonous mushrooms.
What evidence is there for the efficacy of alpha-Lipoic acid?
(i) Diabetes: In patients with type II diabetes, treatment with alpha-lipoic acid reduces insulin resistance and improves glucose balance (Jacob et al, 1995; Jacob et al, 1996; Henriksen EJ, 2006). A number of randomised controlled clinical trials have investigated the effect of alpha-lipoic acid treatment for diabetic neuropathy, using different study designs, treatment duration, dose, mode of administration and patient populations (Zeigler et al, 1995; Zeigler & Gries, 1997; Zeigler et al, 1997; Reljanovic et al, 1999; Ruhnau et al, 1999; Ametov et al, 2003). Both short term and longer term treatments using intravenous or oral administration of alpha-lipoic acid resulted in significant clinical improvement in symptoms (pain, numbness, etc) in peripheral or cardiac neuropathy. These studies also confirmed a favorable safety profile for alpha-lipoic acid.
(ii) Other disorders: Randomised controlled clinical trials have described benefits of alpha-lipoic acid administration for patients with multiple sclerosis (Yadav et al, 2005), glaucoma (Filina et al, 1995) and Burning Mouth Syndrome (Femiano & Scully, 2002).
Are there adverse effects from taking alpha-Lipoic acid?
Alpha-lipoic acid is generally well tolerated, although individuals may rarely suffer from gastrointestinal disturbance or a skin rash. Alpha-lipoic acid is very safe, with no reports of significant adverse effects. The toxicity of alpha-lipoic acid is very low, with an LD50 in rats of 500mg/Kg bodyweight. Patients with diabetes taking alpha-lipoic acid may require modification of their insulin medication.
How much alpha-Lipoic acid should you take?
The generally recommended intake for alpha-lipoic acid is 50 to 150mg/day. For the treatment of specific disorders outlined above, doses of up to 800mg daily may be required.
Ametov AS, Barinov A, Dyck PJ et al (2003) The sensory symptoms of diabetic polyneuropathy are improved with alpha-lipoic acid: the SYDNEY trial. Diabetes Care; 26(7): 770-776.
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