Can a Low-Fat Diet Reverse Neuropathic Pain?

By Pat Anson, PNN Editor

Low fat diets are often recommended for people suffering from obesity and cardiovascular disease, but changes in eating habits are rarely recommended for people who live with chronic pain.

That could be changing thanks to a new study by researchers at the University of Texas Health Science Center, who found that diets high in omega-6 fats are strongly associated with inflammation and neuropathic pain. Omega-6 fats are widely found in typical Western diets of fast food, processed snacks, cakes, and fatty or cured meats.

Conversely, researchers say foods containing healthy omega-3 fatty acids – such as fish, flaxseed and walnuts – could reduce or even reverse neuropathic pain associated with diabetes. Their findings were recently published in the journal Nature Metabolism.

Diabetic neuropathy is a progressive and painful disease that causes burning or stinging sensations in the hands and feet. Many drugs used to treat neuropathic pain, such as gabapentin and pregabalin, often don’t work or have unpleasant side effects.

“This paper is a high-profile contribution for a huge unmet translational need as there are no treatments altering the nature of this neurological disease,” said José Cavazos, MD, director of the South Texas Medical Scientist Training Program at UT Health San Antonio.

In experiments on humans and laboratory animals, UT researchers found that mice fed a diet high in omega-6 polyunsaturated fats became hypersensitive to pain, cold and heat stimulation – signs of peripheral nerve damage. Lowering the amount of omega-6 fats and increasing omega-3 fatty acids reduced pain sensitivity in the mice.

The researchers also found that high levels of omega-6 lipids in the skin of patients with Type 2 diabetes were strongly associated with neuropathic pain and the need for analgesic drugs.

“We believe that these data warrant continued investigation of peripheral fatty acid and metabolite levels as potential pain biomarkers. Such biomarkers could provide clinicians with reliable objective endpoints to guide diagnoses as well as decision making on treatment regimens, including therapeutic diets,” wrote lead author Jacob Boyd, MD, UT Health San Antonio.

About 34 million people in the U.S. have diabetes and about half have some form of neuropathy, according to the American Diabetes Association.

A 2015 study found that a vegetarian diet coupled with vitamin B12 supplements significantly reduced pain and improved the quality of life of people with diabetic neuropathy. Participants also had lower blood pressure and cholesterol levels, and lost an average of 14 pounds.

Lyrica and Cymbalta Advised for Diabetic Neuropathy

By Pat Anson, Editor

New guidelines by the American Diabetes Association for the treatment of diabetic neuropathy strongly discourage the use of opioids to treat nerve pain, while recommending pregabalin (Lyrica) and duloxetine (Cymbalta).

Nearly 26 million people in the United States have diabetes and over half have some form of neuropathy, which often causes a painful stinging or burning sensation in the hands or feet.  Nerve pain is often the first symptom that prompts people to seek medical care before getting a diabetes diagnosis.

Researchers at the University of Michigan led a group of internationally recognized endocrinologists and neurologists, and teamed up with the American Diabetes Association (ADA) to craft a new position statement on the prevention, treatment and management of neuropathy. The ADA last released a statement on diabetic neuropathy in 2005.

"Our goal was to update the document so that it not only had the most up-to-date evidence, but also was easy to understand and relevant for primary care physicians," said lead author Rodica Pop-Busui, MD, a professor of internal medicine at Michigan Medicine Division of Metabolism, Endocrinology and Diabetes.

"Treatment of neuropathy pain is specifically relevant because, unfortunately, there has been much overprescribing of narcotics for neuropathic pain."

Although opioids like oxycodone and tramadol are effective in relieving nerve pain, they are not recommended by the ADA as a first, second or even a third-line treatment.

“Despite the demonstrated effectiveness of opioids in the treatment of neuropathic pain, there is a high risk of addiction, abuse, sedation, and other complications and psychosocial issues even with short-term opioid use. For these reasons, opioids are not recommended in the treatment of painful DSPN (distal symmetric polyneuropathy) before failure of other agents that do not have these associated concerns,” the guideline states.

Instead of opioids, the ADA recommends either pregabalin (Lyrica) or duloxetine (Cymbalta) as an initial treatment for neuropathic pain. Gabapentin (Neurontin) can also be considered.

PNN readers often complain of side effects from all three drugs – such as depression, fatigue, nausea, headache and weight gain -- yet the ADA statement only vaguely warns that their “adverse effects may be more severe in older patients.”

"Lyrica did help with my nerve pain but the side effects were intolerable and the withdrawal was absolute hell," said Laura.  "I gained 20 pounds in a month and was even more of a zombie than when I was on gabapentin. I had no personality, no interest in anything, and had completely lost motivation to do anything."

"I have been on Cymbalta a couple of years. It has helped overall with depression, anxiety and pain. I also can't miss a dose or try to quit cold turkey," wrote Rebecca Williams. "I become very dizzy, nauseated, night sweats, crazy dreams, electrical zaps in my head. I don't know how I would ever get off of it because the withdrawal symptoms are unbearable."

The ADA guidelines recommend that physicians try different therapies to prevent or slow the progression of diabetic neuropathy, most of which focus on controlling high blood sugar (glucose), which can cause irreversible damage to small nerve fibers. Insulin, regular exercise and a low-calorie, low-fat diet can help regulate glucose levels.

To see the ADA’s recommendations, click here.