The Emerging Role of Alpha Lipoic Acid for Diabetic Neuropathy

The term peripheral neuropathy refers to a condition characterized by damage to nerves that are not part of the brain and spinal cord. When this condition is the result of chronic elevated glucose levels it is then referred to as diabetic neuropathy. Research reveals that more than 70% of people with elevated glucose levels (as in pre-diabetes or diabetes) will develop peripheral neuropathy.

The debilitating condition of Diabetic neuropathy now affects an estimated 18 million Americans. Symptoms associated with diabetic neuropathy can be quite aggressive and include pain, loss of sensation (numbness), tingling, weakness and even loss of balance, typically affecting the feet or hands. Alpha-lipoic acid (ALA) is one possible treatment for diabetic neuropathy.

Alpha-lipoic acid (ALA) is a powerful antioxidant that is made by the body and found in every cell. Antioxidants attack “free radicals,” waste products created when the body turns food into energy. Free radicals cause harmful chemical reactions that can damage cells, organs and tissues in the body, making it harder for the body to fight off infections, according to the University of Maryland Medical Center.

Everyone on this planet requires antioxidant protection but this is especially the case with diabetics. They require a stronger source of protection than a healthy individual and ALA fulfills this need. It has a substantial ability to squelch free radicals and aid the liver in the detoxification process. Of significant importance is ALA’s ability to restore vitamin C and E levels, two other important antioxidants helpful in nerve repair.

Benefits of Alpha Lipoic Acid and Diabetes

In several studies, alpha-lipoic acid has been shown to lower blood sugar levels, increase insulin sensitivity and aid in peripheral nerve repair.

As a matter of fact, Alpha-lipoic acid has been used for years to treat peripheral neuropathy in Germany. Both oral and intravenous ALA is approved for use in Germany for treatment of diabetic neuropathy and in the U.S.
In one study, alpha lipoic acid was indeed found to improve insulin sensitivity.

Researchers gave 600mg of controlled-release alpha lipoic acid twice a day to six non-diabetic women with polycystic ovarian syndrome.
At the end of 16 weeks, the women enjoyed a 13.5 percent improvement in insulin sensitivity, as well as lower triglyceride levels.

Finally, a gold standard study—multi-center, randomized, double-blind, placebo-controlled—tested alpha lipoic acid’s benefit for type 2 diabetics with neuropathy.5(Neuropathy, a common complication of type 2 diabetes, is marked by damage to the nerves of the peripheral nervous system.)

Researchers divided 181 diabetics into four groups. As in the aforementioned study, the first received 600mg of alpha lipoic acid a day, the second received 1,200mg a day, the third received 1,800mg a day, and the fourth group received a placebo. However, this group received their dosages all at once, rather than divided throughout the day.
After five weeks, those patients taking the alpha lipoic acid enjoyed significantly greater symptom relief than the placebo group, with an average of 50 percent greater decrease in symptoms across all three alpha lipoic acid groups, as compared to just a 32 percent decrease of symptoms in the placebo group.

Researchers concluded “oral treatment with [alpha lipoic acid] for five weeks improved neuropathic symptoms.”
Along with alleviating symptoms, research also revealed that ALA aided in nerve repair. This occurred by escalating the speed of conduction of the nerve which led to improved nerve communication and proper signaling of muscle fibers. As a result, not only were diabetic neuropathy symptoms decreased, but there was also a halt to muscular atrophy (or wasting). Other notable actions of ALA were a drop in blood glucose levels, an improvement in hemoglobin A1c levels and improvement in microcirculation. The end result, increased wound healing and better blood flow to the legs, hands, eyes, heart and brain.

One 2006 study also found that taking alpha-lipoic acid for diabetic neuropathy reduced symptoms compared to placebo. A study in Austria found that more than half of the cancer patients, that suffered from chemotherapy induced peripheral neuropathy (CIPN), who took ALA after receiving their chemotherapy reported an improvement in neuropathy symptoms.

Taking alpha-lipoic acid may help another diabetes-related condition called autonomic neuropathy, which affects the nerves to internal organs. One study found that 73 people with cardiac autonomic neuropathy, which affects the heart, showed fewer signs of the condition when taking 800 mg of alpha-lipoic acid orally compared to placebo.

Brain Function and Stroke

Because alpha-lipoic acid can pass easily into the brain, it may help protect the brain and nerve tissue. Researchers are investigating it as a potential treatment for stroke and other brain problems involving free radical damage, such as dementia.

Not All Alpha Lipoic Acid Is Created Equally

If you decide to use alpha lipoic acid, make sure you do your homework. There are two forms of alpha lipoic acid: R-alpha lipoic acid and S-alpha lipoic acid.

The R form is alpha lipoic acid in its natural state. It is this form that contains the powerful antioxidant and type 2 diabetes-fighting benefits.

The S form is a synthetic clone of alpha lipoic acid that does not exist naturally and, as a result, it is completely ineffective.

Unfortunately, many commercial alpha lipoic acid products are a 50/50 combination of the R and S forms. So be sure to do your homework and make certain you are getting 100 percent R-alpha lipoic acid.

If the manufacturer doesn’t list the form and appears to be more interested in hype than research, move on to another product.
Also, make sure the manufacturer uses good manufacturing practices (GMP) for the product and be sure you can find all ingredients contained in the product before purchasing. And, if the product contains a trademarked extract, research that extract. Is it safe? Has it been through clinical trials?

Finally, be sure the product you choose is free of preservatives, fillers, binders, excipients, flow agents, shellacs, coloring agents, gluten, yeast, lactose, and other allergens.

Once you have selected a high quality product, the recommended dosage, based on the studies referenced above, is 600mg of alpha lipoic acid a day.

Some side effects with dosages of alpha lipoic acid exceeding 600 mg daily have included nausea, vomiting, and skin rash.

References

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