Inflammatory Disorders: Rheumatoid Arthritis, Osteoarthritis and Omega 3 Essential Fatty Acids;

Since the early 1970’s, “healthy diet” messages have pervaded the United States as a public health measure to reduce the risk of cardiovascular disease. The message was strong; decrease saturated fat intake and replace it with healthy polyunsaturated fats.  But there is now a growing appreciation for the balance of the two major kinds of polyunsaturated fats, the omega 6 and omega 3 varieties, and their potentially vastly different effects on health. 

Because of our current food preferences massively favor high amounts of the omega 6 fatty acids, the ratio of omega 6 to omega 3 fats in our diet is now around 25 to 1. Arachidonic acid, a physiologically significant omega 6 fatty acid, is the precursor for prostaglandins and other physiologically active inflammatory molecules.

Research has suggested that excessive levels of omega 6 fatty acids, relative to omega 3 fatty acids, may increase the probability of many disease states. Modern Western diets typically contain an omega 6 to omega 3 ratio greater than 30 to 1. Again the optimal ratio should be approximately a 1 to 1 ratio.

Observational studies have demonstrated that diets high in Omega 3's and low in Omega 6's confer significant health benefits.  The Greenland Eskimos, for instance, have a ratio of omega 6 to omega 3 fatty acids approximating 1 to 1, which is associated with an extremely low rate of heart attacks and very low rates of diseases involving inflammation such as psoriasis, asthma and arthritis.  Similarly, the traditional Japanese diet, high in omega 3 fat intake, correlates with low rates of heart disease and rheumatoid arthritis.

These epidemiological observations have driven research on the effects of fish oil on other diseases involving inflammation.  Rheumatoid arthritis is one such disorder and the central symptomatic issue in rheumatoid arthritis is chronic and excessive inflammation of the joints. Could such a devastating and disabling chronic illness benefit from increased Omega 3 intake? 

Twelve (12) double-blind, placebo-controlled dietary intervention studies with omega 3 fatty acids, in the form of fish oil capsules, demonstrated a significant degree of clinical benefit in rheumatoid arthritis. Durations of these studies varied from 12 to 52 weeks and the amount of omega 3 fatty acids ingested varied from 1 to 7.1 grams. 

Among these clinical trials, at least two of the following outcomes measures improved in each study: number of tender joints, number of swollen joints, duration of morning stiffness, grip strength, as well as patient and physician global health assessment.

Also, fish oil intake led to decreased anti-inflammatory drug use in three of the eleven studies in which it was measured. One significant feature of these omega 3 fish oil studies is that they were conducted in a double-blind, placebo-controlled manner.

Randomizing some patients to take fish oil, and others to take a “placebo” oil, with neither patient nor investigator knowing which oil is being taken, allows for the most accurate level of scientific measurement and effect.   This important aspect of the fish oil studies is a requirement for any sound study of experimental treatments. 

Although research regarding the use of omega 3 fatty acid supplements for inflammatory joint conditions has focused almost entirely on rheumatoid arthritis, relatively recent research also suggests that diets rich in omega 3 fatty acids (and low in omega 6 fatty acids) may benefit people with other inflammatory disorders, such as Osteoarthritis.  In fact, several laboratory studies of cartilage-containing cells have found that omega 3 fatty acids decrease inflammation and reduce the activity of enzymes that break down cartilage.

Additionally, a study by Curtis et al in 2002 demonstrated that supplementation with Omega 3 fatty acids, but not omega 6 fatty acids, caused a decrease in both the degradative and inflammatory aspects of cartilage metabolism. The Curtis et al study provides evidence supporting the assertion that dietary supplementation of omega 3 fatty acids may have a beneficial effect of slowing and reducing inflammation in the pathogenesis of degenerative joint diseases in man.

Another study by Caterson et al 2006 revealed that pathologic indicators manifested in human osteoarthritis cartilage can be significantly altered by exposure of the cartilage to omega-3 fatty acids, but not to other classes of fatty acids.