Other names: lipoic acid, thioctic acid, ALA
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.
Why People Use Alpha Lipoic Acid
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 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.
Alpha lipoic acid has also been suggested for cataracts, glaucoma, 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.
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.