New Hope for Relief from Diabetic Neuropathy

It’s one of the most common complications of diabetes:

Nerve damage known as diabetic neuropathy.¹

About 30% to 50% of individuals with type II diabetes will develop this debilitating condition, often in the legs and feet.²

Diabetic neuropathy frequently causes severe pain and loss of mobility. When the condition worsens, it can lead to amputation and even fatal infections.^3,4

By the time symptoms arise, the nerve damage has already progressed and become severe–and very difficult to fully repair.

That makes it crucial for diabetics to take aggressive measures to prevent the horrors of diabetic neuropathy.

Managing this disorder is challenging. Damage can continue even if sugar levels are under control,^2,5,6 and no drug can reliably stop the nerve damage from getting worse.⁵

Increasing evidence has identified seven nutrients that may provide relief from symptoms and protect against the development of diabetes-induced neuropathy.^7-23 They are:

• Omega-3 fatty acids
• Vitamin D
• Curcumin
• Lipoic acid
• Folic acid
• Acetyl-L-carnitine
• Benfotiamine

Working in overlapping ways, each of these compounds protects tiny nerves through important mechanistic pathways.

What Is Diabetic Neuropathy?

Diabetic neuropathy occurs when prolonged elevation of blood sugar levels damages tiny capillaries feeding blood to nerve fibers.

As nerves shrivel and die from lack of blood flow, there is a loss of nerve function, loss of sensation in affected areas, and progressive manifestation of pain and immobility.

There are several types of diabetic neuropathy, categorized by which nerves are affected.

Diabetic neuropathy occurs in both type I and type II diabetes, and about 40% to 70% of diabetics will develop the condition.^24-28

Symptoms depend on the type of neuropathy and which nerves are affected. Usually the symptoms develop gradually, and can include severe pain, numbness or tingling of extremities, balance problems, erectile dysfunction, and more.²⁹

Published research indicates how seven nutrients can offer relief of symptoms and even slow the processes that lead to nerve dysfunction.^7-23

Omega-3 Fatty Acids

Fish and flaxseed oils are rich in anti-inflammatory omega-3 fatty acids.

Increasing intake of omega-3s shows great promise in preventing and relieving diabetic neuropathy. In rodent studies, fish oil can slow and even reverse the progression of diabetic nerve damage.^22,23

Here are some critical ways in which omega-3s may help treat diabetic neuropathy:

• People with diabetic neuropathy suffer from a decrease in nerve conduction velocity, which measures how fast an electrical impulse moves through the nerves. In animals, fish oil rapidly restores nerve conduction velocity and reduces visible damage to crucial nerve bundles.³⁰

• Pain and hypersensitivity to touch are reduced in diabetic animals after treatment with fish oil.³¹

• Nerve clusters from fish-oil-treated animals show a reduction in inflammation, and lower levels of the “master inflammation promoter” nuclear factor kappa B (NF-kB).³¹

• After treatment with DHA or EPA, nerve cells in lab cultures sharply ramp up their production of proteins that fight harmful oxidative stress.³²

The above differing actions have major consequences. In a study of people with diabetic foot ulcers, complications of neuropathy that can lead to amputation, taking one gram per day of omega-3 significantly decreased ulcer size.

At the same time, markers of inflammation were lower and total antioxidant levels rose significantly.³³

Vitamin D

Vitamin D is best known for its role in building strong bones. But it also has an important impact on brain and nerve tissue.^34,35

Numerous studies have established that vitamin D deficiency (levels less than 20 ng/mL) and insufficiency (20 ng/mL to 30 ng/mL) are strongly associated with neuropathy in diabetics.^1,36-38

One study found that diabetics with deficient vitamin D levels have two-fold greater odds of neuropathy.³⁷

Clinical trials have established that 50,000 IU of vitamin D3 weekly significantly reduces symptoms of diabetic nerve damage and improves quality of life.^18,19

And in one study, 50,000 IU of vitamin D given every two weeks significantly reduced the size of diabetic foot ulcers after 12 weeks.³⁹

Curcumin

Curcumin is prized for its anti-inflammatory properties and has recently been studied for its potential in pain control.^40,41

In fact, curcumin has been shown to significantly raise the pain threshold and reduce pain hypersensitivity in lab animals.^41-44

For people suffering from diabetic nerve damage, curcumin offers much more than pain relief. The compound, found in the spice turmeric, may also slow or reverse some of the processes that produce neuropathic pain in the first place.

Pre-clinical studies show that curcumin:

• Reduces production of TNF-alpha, an inflammatory protein and contributor to pain,⁴³

• Activates the internal pain-relief system (known as the endogenous opioid system),⁴¹

• Inhibits oxidative stress in cells, which is a major trigger of nerve pain,⁴⁴ and

• Reduces aberrant electrical impulses in diabetic nerves.^45,46

Lipoic Acid

A number of human studies show that in diabetes patients with painful nerve damage, 600 mg daily of alpha-lipoic acid produces significant improvements in:^14-17

• Pain,
• Burning,
• Numbness,
• Ability to feel pin pricks and touch pressure,
• Ankle reflexes,
• Muscle weakness,
• Need for “rescue” pain medications,
• Quality of life scores, and
• Reports of overall health status.

At the same dose, alpha-lipoic acid also prevents worsening of impairment caused by neuropathy.¹⁵

Folic Acid

Folic acid is a B vitamin that lowers levels of homocysteine,⁴⁷ an amino acid that is linked to the development of cardiovascular disease and is dangerously toxic to nerves.⁴⁸

In a 2001 study involving 65 patients with type II diabetes, the risk of nerve damage more than doubled with each 5 mmol/L increase in homocysteine.⁴⁹

Chinese patients who have type II diabetes with neuropathy also have significantly lower levels of folate than those without neuropathy.⁵⁰

A recent study of patients with diabetic neuropathy showed that 1,000 mcg of folic acid given daily for 16 weeks, lowered homocysteine levels, and markedly increased nerve conduction velocity and signal strength.¹³

An animal study found that folic acid treatment could protect against neuropathy by increasing nerve growth factor, a protein essential for promoting nerve healing.⁵¹

Acetyl-L-Carnitine

Acetyl-L-carnitine is a form of the amino acid L-carnitine that has shown to have neuroprotective and analgesic effects in the peripheral nervous system.⁵²

Acetyl-L-carnitine works in multiple ways to protect nerves, including:⁵³

• Reducing harm from oxidative stress and helping to prevent nerve cell death,

• Relieving pain by reducing the concentration of the pain-signaling neurotransmitter glutamate at the synapses,

• Facilitating nerve regeneration and nerve damage repair,

• Promoting the health of nerve cell membranes, and

• Amplifying responses to nerve growth factor.

In people with diabetes, acetyl-L-carnitine at doses of 1,500 mg/day to 3,000 mg/day improves nerve conduction velocity and strength, reduces pain and disability scores, increases numbers of nerve fibers, and regenerates damaged nerve fibers.^10-12

Benfotiamine

Benfotiamine is the fat-soluble form of thiamine (vitamin B1).

One key factor involved in the development and progression of diabetic neuropathy is increased glycation, a process in which glucose and other sugars interact with proteins.

Glycation is a process in which glucose and other sugars bind irreversibly to proteins, lipids and nucleic acids, causing them to become dysfunctional. The dysfunctional molecules created by glycation are known as advanced glycation end products (AGEs).^54-56

AGEs damage nerves by inhibiting their function, which in turn affects their activity, and by triggering an inflammatory response that further damages nerve cells.⁵⁷

Studies have shown that benfotiamine reduces pain and restores normal sensation in patients suffering from diabetic neuropathy.^7-9

The best results have been seen with doses ranging from 320 mg to 600 mg daily, for periods as short as three weeks, though benefits steadily increased with longer treatment duration.^7-9

Summary

Diabetic neuropathy—nerve damage resulting from diabetes—can lead to severe pain, numbness, loss of function, and even limb amputation.

No drug can reliably stop or reverse the progression of diabetic neuropathy.

Seven nutrients may be capable of slowing the progression of diabetic neuropathy.

They work in many ways, offering a broad range of protection against this debilitating ailment.

If you have any questions on the scientific content of this article, please call a Life Extension^® Wellness Specialist at 1-866-864-3027.

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