Fatty acids are the building blocks of our nerve cell membranes.  Because of this, dietary fatty acids have a powerful influence on our experience of pain.

There are two major ways that fats affect the nerve fibers that govern pain.  One is by forming the basic structure of the covering of nerves (nerve cell membranes).  Fatty acids can be seen as the building blocks of nerve cell membranes, much like bricks, wood, or cement blocks are the building blocks of our homes.  The other way that fatty acids influence nerve fibers and pain has to do with a substance called myelin.  Myelin is an insulating sheath that surrounds certain nerve fibers for the purpose of speeding up the speed at which impulses are sent.  Myelin can be loosely viewed like the insulation on a wire.  Myelin is built from certain types of fat and is strongly influenced by the type of fatty acids in the diet.   

To gain control over joint symptoms, we want to make sure that there are no structural defects in the nerve fibers that would influence the perception of pain.  This must take into consideration the building blocks of nerves:  fatty acids.  More precisely, we want to ensure that pain fibers from injured joints are not firing improperly due to fatty acid deficiency.

[INSERT GRAPHIC OF FATTY ACIDS IN NEURON CELL MEMBRANE]

[INSERT GRAPHIC OF NERVE CELL MYELIN AND FATTY ACIDS]

Fatty Acids and Nerve Fibers

While the link to fatty acids and nerves has been known for some time, we have new evidence that fatty acid intake can affect the integrity of nerves in the arms and legs over time.  For example, in a 2007 study published in the European Journal of Neurology, doctors wanted to see if the levels of omega-3 and omega-6 fatty acids predicted how nerves in the legs would deteriorate over the next three years. They studied people between the ages of 24 and 97. They measured something called nerve conduction velocity (NCV) and compared those measurements to blood levels of omega-3 and omega-6 fatty acids.  After three years, they found the following were linked to accelerated decline in function of the peroneal nerve in the legs:

• Lower blood unsaturated fatty acids
• Altered omega-6/omega-3 ratio
• Lower DHA  levels 

In general, lower blood fatty acids were associated with "accelerated decline of peripheral nerve function with aging."
[Lauretani, F, Bandinelli, S, Bartali, B, et al. Omega-6 and omega-3 fatty acids predict accelerated decline of peripheral nerve function in older persons. Eur J Neurol 2007;14(9):1071.]

This is not unexpected.  In one study, rats with injured sciatic nerves that consumed corn oil and other omega-6 oils had evidence of more pain.  Omega-3 fatty acids were associated with less pain.  They wrote, "We found that certain commonly used oils can have a significant analgesic effect in rats with persistent pain after partial nerve injury. This effect may be associated with the amounts of omega-3 fatty acids consumed by rats." [Perez, J, Ware, MA, Chevalier, S, et al. Dietary omega-3 fatty acids may be associated with increased neuropathic pain in nerve-injured rats. Anesth Analg 2005;101(2):444-8.]
 

Do Fatty Acid Supplements Help Pain?

Doctors have become increasingly impressed with the capacity of fatty acids to affect nerves and improve pain tolerance.

In one recent attempt to clarify the role of fatty acids, doctors analysed 17 separate studies to address the question of whether consuming omega-3 fatty acids affected joint pain.  This was published in the journal Pain in 2007.  They looked at the following outcomes: (1) patient assessed pain, (2) physician assessed pain, (3) duration of morning stiffness, (4) number of painful and/or tender joints, (5) Ritchie articular index, and (6) nonselective nonsteroidal anti-inflammatory drug consumption.  Supplementation with omega-3 PUFAs for up to four months reduced patient reported joint pain intensity, minutes of morning stiffness, number of painful and/or tender joints, and use of anti-inflammatory drugs. The doctors noted that omega-3 fatty acids were "an attractive adjunctive treatment for joint pain."
[Goldberg, RJ, Katz, J. A meta-analysis of the analgesic effects of omega-3 polyunsaturated fatty acid supplementation for inflammatory joint pain. Pain 2007;129(1-2):210-23.]

Keeping the ratio of omega-6 to omega-3 fatty acids in balance is important to controlling pain and inflammation. This is true for joints, as well.  In one study, people who had joint pain and inflammatory bowel disease were given a seal oil supplement, which has a composition somewhat similar to fish oil--rich in omega-3 fatty acids.  The seal oil supplement normalized the omega-3 fatty acid levels and improved the omega-6 to omega-3 fatty acid ratio.  Of importance was the finding that the omega-3 rich supplement "improved the bodily pain dimension of patients with IBD-related joint pain." [Bjorkkjaer, T, Brun, JG, Valen, M, et al. Short-term duodenal seal oil administration normalised n-6 to n-3 fatty acid ratio in rectal mucosa and ameliorated bodily pain in patients with inflammatory bowel disease. Lipids Health Dis 2006;5:6.]

Perhaps one of the most compelling studies appeared in the journal Surgical Neurology in 2006. Doctors followed 250 patients who had neck or back pain.  The patients were asked to take EPA and DHA from fish oil for a period of over two months.  Of those that returned the symptom and quality of life questionnaires:

• 59 percent stopped their prescription NSAID medications for pain
• 60 percent stated that their overall pain was improved
• 60 percent stated that their joint pain had improved
• 80 percent stated they were satisfied with their improvement
• 88 percent stated they would continue to take the fish oil
• There were no significant side effects reported

This study should be encouraging to all people who suffer pain symptoms.  It should also be considered by all doctors who wish to reduce pain and reduce anti-inflammatory drug use in their patients.  The authors of this study at the University of Pittsburgh wrote of their findings: "Our results mirror other controlled studies that compared ibuprofen and omega-3 EFAs [fatty acids] demonstrating equivalent effect in reducing arthritic pain. Omega-3 EFA fish oil supplements appear to be a safer alternative to NSAIDs for treatment of nonsurgical neck or back pain in this selective group." [Maroon, JC, Bost, JW. Omega-3 fatty acids (fish oil) as an anti-inflammatory: an alternative to nonsteroidal anti-inflammatory drugs for discogenic pain. Surg Neurol 2006;65(4):326-31.]
 

  Which Fatty Acids are Best?

Nerve cell membranes require a variety of different fatty acids.  However, modern diets tend to have an excess of omega-6 fatty acids, while being deficient in omega-3 fatty acids. Omega-6 fatty acids are found in corn, sunflower, safflower, and sesame oil.  The omega-3 fatty acids are EPA and DHA are found in fish oil, krill oil, and other cold water species.  Another omega-3 fatty acid, alpha-linolenic acid, is found in flax oil, walnuts, and pumpkin seed oil.  EPA and DHA are especially critical for preserving nerve cell integrity.  Therefore, many doctors now recommend that people with pain symptoms use fish oil or krill oil to get their daily omega-3 fatty acids. Weekly consumption of cold water fish is another way to get these fatty acids.