Also indexed as: ALA, Lipoic Acid, Thioctic Acid
What does it do?
Alpha lipoic acid (ALA) is a vitamin-like
antioxidant, sometimes referred to as the “universal antioxidant” because it
is soluble in both fat and water.1
ALA is manufactured in the body and is found in some foods, particularly liver and yeast.
ALA is capable of regenerating several other antioxidants back to their active states,
including vitamin C,2 vitamin E,3
glutathione,4 and coenzyme
Q10.5
ALA has several potential benefits for people with diabetes. It enhances glucose uptake in
type 2 (adult onset or non-insulin-dependent) diabetes,
inhibits glycosylation (the abnormal attachment of sugar to protein), and has been used to
improve diabetic nerve damage and reduce pain associated with that nerve damage.6
Most studies have used intravenous alpha lipoic acid, but oral supplementation has nonetheless
proved partially helpful in treating at least one form of diabetic neuropathy, using 800 mg
per day.7
Preliminary evidence indicates that 150 mg of alpha lipoic acid, taken daily for one month,
improves visual function in people with
glaucoma.8
ALA has been shown to inhibit the replication of the
HIV virus in the test tube; however, it is not known whether supplementing with ALA would
benefit HIV-infected people.9
Intravenous administration of ALA has significantly increased the survival rate of people
who have eaten poisonous mushrooms.10 Such a treatment should be prescribed by a
doctor and should not be attempted on one’s own.
Where is it found?
The body makes small amounts of alpha lipoic acid. There is only limited knowledge about
the food sources of this nutrient. However, foods that contain mitochondria (a specialized
component of cells), such as red meats, are
believed to provide the most alpha lipoic acid. Supplements are also available.
Alpha lipoic acid has been
used in connection with the following conditions (refer to the
individual health concern for complete information):
Who is likely to be deficient?
Although alpha lipoic acid was thought to be a vitamin when it was first discovered,
subsequent research determined that it is created in the human body—and thus is not an
essential nutrient. For this reason, deficiencies of alpha lipoic acid are not known to occur
in humans.
How much is usually taken?
The amount of alpha lipoic acid used in research to improve diabetic neuropathies is 800 mg
per day and 150 mg per day for glaucoma. However, much
lower amounts, such as 20–50 mg per day, are recommended by some doctors for general antioxidant protection, although there is no clear
evidence that such general use has any benefit.
Are there any side effects or interactions?
Side effects with alpha lipoic acid are rare but can include skin rash and the potential of
hypoglycemia in diabetic patients. People who may be
deficient in vitamin B1 (such as alcoholics) should take
vitamin B1 along with alpha lipoic acid supplements. Chronic administration of alpha lipoic
acid in animals has interfered with the actions of the vitamin,
biotin. Whether this has significance for humans remains unknown.11
At the time of writing, there were no well-known drug interactions
with alpha lipoic acid.
References
1. Kagan V, Khan S, Swanson C, et al. Antioxidant action of thioctic acid
and dihydrolipoic acid. Free Radic Biol Med 1990;9S:15.
2. Lykkesfeldt J, Hagen TM, Vinarsky V, Ames BN. Age-associated decline
in ascorbic acid concentration, recycling, and biosynthesis in rat hepatocytes—reversal
with (R)-alpha-lipoic acid supplementation. FASEB J 1998;12:1183-9.
3. Scholich H, Murphy ME, Sies H. Antioxidant activity of dihydrolipoate
against microsomal lipid peroxidation and its dependence on alpha-tocopherol. Biochem
Biophys Acta 1989;1001:256-61.
4. Busse E, Zimmer G, Schorpohl B, et al. Influence of alpha-lipoic acid
on intracellular glutathione in vitro and in vivo.
Arzneimittelforschung1992;42:829-31.
5. Kagan V, Serbinova E, Packer L. Antioxidant effects of ubiquinones in
microsomes and mitochondria are mediated by tocopherol recycling. Biochem Biophys Res
Commun 1990;169:851-7.
6. Packer L, Witt EH, Tritschler HJ. Alpha-lipoic acid as a biological
antioxidant. Free Radic Biol Med 1995;19:227-50 [review].
7. Ziegler D, Ulrich H, Schatz H, et al. Effects of treatment with the
antioxidant alpha-lipoic acid on cardiac autonomic neuropathy in NIDDM patients. Diabetes
Care 1997;20:369-73.
8. Filina AA, Davydova NG, Endrikhovskii SN, et al. Lipoic acid as a
means of metabolic therapy of open-angle glaucoma. Vestn Oftalmol 1995;111:6-8.
9. Baur A, Harrer T, Peukert M, et al. Alpha-lipoic acid is an effective
inhibitor of human immuno-deficiency virus (HIV-1) replication. Klin Wochenschr
1991;69:722-4.
10. Nichols TW Jr. Alpha-lipoic acid: biological effects and clinical
implications. Altern Med Rev 1997;2:177-83 [review].
11. Zempleni J, Trusty TA, Mock DM. Lipoic acid reduces the activities of
biotin-dependent carboxylases in rat liver. J Nutr 1997;127:1776–81.
Copyright © 2003 Healthnotes, Inc. All rights reserved.
www.healthnotes.com
Learn more about Healthnotes, the company.
Learn more about the authors of Healthnotes.
The information presented in Healthnotes is for informational
purposes only. It is based on scientific studies (human, animal, or in vitro),
clinical experience, or traditional usage as cited in each article. The results reported may
not necessarily occur in all individuals. For many of the conditions discussed, treatment with
prescription or over-the-counter medication is also available. Consult your doctor,
practitioner, and/or pharmacist for any health problem and before using any supplements or
before making any changes in prescribed medications. Information expires July 2004.
Contradictory, insufficient, or preliminary
studies suggesting a health benefit or minimal health benefit.