What is alpha-lipoic acid?
Alpha-lipoic acid (also known as ALA) is a synthetic version of lipoic acid, a naturally occurring compound produced in the body and synthesized by both plants and animals. This antioxidant is vital to cellular energy production, and helps to neutralize the damage caused by free radicals. Free radicals are chemical byproducts produced during the process of oxidation that converts nutrients to cellular energy. As they oxidize, these compounds can become highly reactive and harmful to the cell, distorting its vital components and reducing its metabolic efficiency. While the body can naturally manufacture enough lipoic acid for metabolic functions, supplementing can allow more optimal levels to circulate in a free state.
Why is it necessary?
As a dietary supplement, alpha-lipoic acid appears to help increase insulin sensitivity, and may be especially useful in addressing metabolic syndrome. In addition, ALA works with other antioxidants to help neutralize free radicals and reduce cellular damage. It also acts as a synergist with B vitamins to help in the production of energy from the proteins, carbohydrates and fats consumed through foods. Researchers have investigated the use of alpha-lipoic acid in the treatment of diabetic neuropathy, liver ailments and glaucoma. It may improve memory via its protective effects on brain and nerve tissue.
What are the signs of a deficiency?
Because lipoic acid works synergistically with many other nutrients, deficiency symptoms for this substance alone are difficult to characterize or diagnose. A true deficiency can mimic the general symptoms of inadequate antioxidant activity, including weakened immune function, decreased muscle mass and memory problems.
How much, and what kind, does an adult need?
Currently there are no established daily doses for supplementation. However, oral alpha-lipoic acid is reported to be well tolerated in doses up to 600 milligrams per day, and 200-300 mg a day is frequently used in Europe as a therapeutic adjunct in treating diabetic neuropathy. As a general antioxidant, a dosage of 20 to 50 mg daily is commonly recommended. Alpha-lipoic acid can be purchased in dosages ranging 30 mg to 100 mg tablets. Talk with your doctor about how much alpha-lipoic acid you should take, and follow package directions.
How do you get enough from foods?
Lipoic acid is present in both plants and animals and is an integral component of the photosynthetic process of chloroplasts. Very small quantities of lipoic acid are contained in food sources such as spinach.
Are there any risks associated with too much?
Alpha-lipoic acid is very safe at commonly recommended dosages. The Physicians Desk Reference reports no known contraindications and no reports of overdosage. However, some evidence suggests that high doses of alpha-lipoic acid may contribute to thiamin deficiency. Minor side effects may include allergic reactions such as itching or hives, headache, muscle cramps and skin rash.
Are there any other special considerations?
Persons undergoing chemotherapy, and those with diabetes or taking anti-diabetes drugs should check with their doctor before taking alpha-lipoic acid or any other supplement. Pregnant and lactating women are advised not to consume alpha-lipoic acid, due to a lack of long-term safety data.
Updated by: Andrew Weil, M.D., and Brian Becker, M.D., on Sept. 7, 2012
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