Other names: lipoic acid, thioctic acid, ALA
Definition: Alpha lipoic acid is a fatty acid found naturally inside every cell in the body. It’s needed by the body to produce the energy for our body’s normal functions. Alpha lipoic acid converts glucose (blood sugar) into energy.
Alpha lipoic acid is also an antioxidant, a substance that neutralizes potentially harmful chemicals called free radicals. What makes alpha lipoic acid unique is that it functions in water and fat, unlike the more common antioxidants vitamins C and E, and it appears to be able to recycle antioxidants such as vitamin C and glutathione after they have been used up. Glutathione is an important antioxidant that helps the body eliminate potentially harmful substances. Alpha lipoic acid increases the formation of glutathione.
Alpha lipoic acid is made by the body and can be found in very small amounts in foods such as spinach, broccoli, peas, Brewer’s yeast, brussel sprouts, rice bran, and organ meats. Alpha lipoic acid supplements are available in capsule form at health food stores, some drugstores, and online. For maximum absorption, the supplements should be taken on an empty stomach.
It is an antioxidant that is manufactured in the human body. Antioxidants are substances that work by attacking “free radicals,” waste products created when the body turns food into energy. There are also many sources of free radicals in the environment such as ultraviolet rays, radiation, and toxic chemicals in cigarette smoke, car exhaust, and pesticides. Free radicals cause harmful chemical reactions that can damage cells in the body, making it harder for the body to fight off infections. As a result a person becomes more susceptible to long term diseases such as diabetes and liver damage.
Peripheral neuropathy can be caused by injury, nutritional deficiencies, chemotherapy or by conditions such as diabetes, Lyme disease, alcoholism, shingles, thyroid disease, and kidney failure. Symptoms can include pain, burning, numbness, tingling, weakness, and itching.
Alpha lipoic acid is thought to work as an antioxidant in both water and fatty tissue, enabling it to enter all parts of the nerve cell and protect it from damage.
Preliminary studies suggest that alpha lipoic acid may help. In one of the largest studies on the use of alpha lipoic acid, 181 people took 600 mg, 1200 mg or 1800 mg of alpha lipoic acid a day or a placebo. After 5 weeks, alpha lipoic acid improved symptoms. The dose that was best tolerated while still providing benefit was 600 mg once daily.
Alpha-lipoic acid works together with other antioxidants such as vitamins C and E. It is important for growth, helps to prevent cell damage, and helps the body rid itself of harmful substances
Several studies suggest that treatment with ALA may help reduce pain, burning, itching, tingling, and numbness in people who have nerve damage (called peripheral neuropathy) caused by diabetes. Alpha-lipoic acid has been used for years for this purpose in Europe. Other studies have shown that alpha-lipoic acid speeds the removal of glucose (sugar) from the blood of people with diabetes and that this antioxidant may prevent kidney damage associated with diabetes in animals.
Alpha-lipoic acid may prove useful in the treatment of chronic hepatitis because it relieves stress on the liver and helps rid the body of toxins. There have been several case reports of use of alpha-lipoic acid in combination with silymarin (milk thistle) and selenium (a substance with liver-protecting and antioxidant properties) to help treat hepatitis C (a serious type of hepatitis contracted from blood and bodily fluids that does not have an adequate cure or treatment).
It has also been used in conjunction with silymarin to treat Amanita poisoning. Amanita is a highly poisonous mushroom that causes liver damage.
*Brain Function and Stroke
Because alpha-lipoic acid can pass easily into the brain, it has protective effects on brain and nerve tissue and shows promise as a treatment for stroke and other brain disorders involving free radical damage. Animals treated with alpha-lipoic acid, for example, suffered less brain damage and had a four times greater survival rate after a stroke than the animals who did not receive this supplement. While animal studies are encouraging, more research is needed to understand whether this benefit applies to people as well.
Alpha lipoic acid can cross the blood-brain barrier, a wall of tiny vessels and structural cells, and pass easily into the brain. It is thought to protect brain and nerve tissue by preventing free radical damage.
As an antioxidant, alpha lipoic acid can neutralize free radicals which can damage cells. Free radical damage is thought to contribute to aging and chronic illness.
Additional conditions for which alpha-lipoic acid may prove useful include heart failure, human immunodeficiency virus (HIV), cataracts, and glaucoma. More research is underway in these areas.
Alpha lipoic acid has also been suggested for cataracts, multiple sclerosis, burning mouth syndrome, Alzheimer’s disease and stroke, but large, well-designed studies are needed to see if it’s effective for these conditions.
Good food sources of alpha-lipoic acid include spinach, broccoli, beef, yeast (particularly Brewer’s yeast), and certain organ meats (such as the kidney and heart.)
Alpha-lipoic acid supplements are available in capsule form.
How to Take It
There are no known scientific reports on the pediatric use of alpha-lipoic acid. Therefore, it is not currently recommended for children.
Alpha-lipoic acid can be purchased in dosages ranging 30 mg to 100 mg tablets. Currently there are no established recommended doses for supplementation. For general antioxidant support, the recommended dose of ALA is 20 mg to 50 mg per day.
Manufacturers of alpha-lipoic acid suggest one or two 50-mg capsules daily as a dietary supplement.
Studies that have been successful in improving nerve function in diabetics have used 600 mg of alpha-lipoic acid per day in divided doses.
Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable healthcare provider. This is especially true for those who are pregnant or breastfeeding.
Skin rash has been reported rarely from alpha-lipoic acid.
Finally, because alpha-lipoic acid has been associated with improved blood sugar control, people with diabetes should follow their blood sugar levels carefully when taking this supplement in order to avoid hypoglycemia (low blood sugar). Your doctor may decide that a reduction in dosage of insulin or oral blood sugar-lowering drugs is needed if you are taking this supplement.
Side effects of alpha lipoic acid may include headache, tingling or a “pins and needles” sensation, skin rash, or muscle cramps.
There have been a few reports in Japan of a rare condition called insulin autoimmune syndrome in people using alpha lipoic acid. The condition causes hypoglycemia and antibodies directed against the body’s own insulin without previous insulin therapy.
The safety of alpha lipoic acid in pregnant or nursing women, children, or people with kidney or liver disease is unknown.
Possible Drug Interactions:
Alpha lipoic acid may improve blood sugar control, so people with diabetes who are taking medication to lower blood sugar, such as metformin (Glucophage), glyburide (DiaBeta, Glynase), should only take alpha lipoic acid under the supervision of a qualified health professional and have their blood sugar levels carefully monitored.
Animal studies indicate that alpha lipoic acid may alter thyroid hormone levels, so it could theoretically have the same effect in humans. People taking thyroid medications such as levothyroxine should be monitored by their healthcare provider.
If you are currently being treated with any of the following medications, you should not use alpha-lipoic acid without first talking to your healthcare provider.
Amikacin and Gentamicin
In an animal study, alpha-lipoic acid supplements reduced side effects, particularly toxicity to the ear, associated with these antibiotics. Additional studies are needed to confirm these effects in people.
Cisplatin and Cyclophosphamide
The use of alpha-lipoic acid supplements in animals protected against toxic side effects associated with these medications.
Thyroid-regulating Medications, Levothyroxine
Rats given alpha-lipoic acid supplements had altered thyroid hormone function, but improved cholesterol levels. Blood hormone levels and thyroid function tests should be monitored closely in people taking thyroid hormones who are also taking alpha-lipoic acid.