Effects of Omega-3 Fish Oils Against Rheumatism

Rheumatoid arthritis (RA) is a chronic disease affecting about 1% of the population, women three times more often than men. About 80% develop the disease between the ages of 35 and 50. Family studies indicate that RA is a hereditary disease. About 79% of people with the genetic code of HLA-DR4 develop RA compared to only 28% of those with other constitutions. However, genetic risk factors cannot fully account for the incidence of RA, suggesting that dietary habits and other environmental factors also play a role in the etiology of the disease. Even if the Japanese population is genetically exposed to the same risk of getting RA as the Western population the prevalence of the disease is much lower (1). Dietary habits may influence the risk of acquiring the disease and may also influence the course and symptoms related to the disease.

Inhabitants of Greenland and the Faroe Islands have less rheumatic problems compared to people in the Nordic region. A cohort study in these two populations revealed that RA occurred with prevalence similar to elsewhere in the World. But the clinical picture and the long-term outcome of the disease were quite different. Patients with an overt clinical picture of RA and a history of 10-30 years were working full time in the fishing industry with exposure to a cold and humid environment. Even more interesting x-ray pictures of their hands showed very little joint deformations. And they had only traces of inflammatory cytokines (IL-1 and TNF) in plasma, laboratory parameters that are constantly elevated in these patients.

The inhabitants of Greenland, the Faroe Islands and the coastal population of Japan have easily access to fish and seafood is accepted as very healthy. In seafood and sea mammals we find the omega-3 fatty acids known to interfere with a series of inflammatory events in the human body protecting against RA and other autoimmune diseases.

The London Medical Journal published the first scientific publication on effects of fish oil against rheumatism in 1783 describing the current practice at Manchester Infirmary. This report was based on positive observations in a disease with no treatment at that time.
However, the modern documentation on omega-3 fatty acids in rheumatic disease comprise well designed, controlled studies showing positive effects on symptoms such as pain, morning stiffness and grip strength. A meta-analysis on all these studies has been published (2) and recommendations on dose have been given (3).

The modern basis for treatment of patients with RA constitutes a combination of symptom treatment and prevention of joint deformation. Symptom relief increase quality-of-life but even more important is prevention of joint destruction, which inevitably will lead to reduced function and invalidity. Pharmacological treatment reduces or prevents negative effects of compounds released by the immune system responsible for the disease. Potent pharmaceuticals have been developed which may change the long-term outcome for RA. However, the omega-3 fatty acids from fish oil, EPA and DHA do the same thing as the pharmaceuticals. The mode-of-action may be different and the potency lower but the effects brought about is certainly more natural compared to the drugs. This may explain why treatment with omega-3 capsules is usually well tolerated with no risk of serious side effects. It has also been demonstrated that omega-3 fatty acids reduce the cartilage destructing enzymes responsible for joint destruction (4). This finding is very important and places omega-3 fatty acids as a natural supplement in combination with anti-rheumatic drugs.

A therapeutic effect on RA utilizing omega-3 fatty acids cannot be achieved by means of increasing the number of fish meals only. A high-quality omega-3 concentrate in the dose of 3g or more daily should be used. Clinical response will not occur immediately but will start after 2-3 months and may even increase further during chronic use (5). At the same time the intake of red meat (high in AA and saturates) should be restricted (2). Omega-3 capsules may be used concomitantly with antirheumatic pharmaceuticals, which may increase efficacy or even reduce the risk of gastrointestinal discomfort, which is a regular problem for so called NSAID drugs (6). For people with only minor or transient joint problems omega-3 fatty acids could be the first choice for self-medication.

Reference:
1) Shichikawa K et al. Ryumachi. Prevalence of rheumatoid arthritis in the Japanese population 1981;21:35-43.

2) Fortin PR et al. Validation of a meta-analysis: The effects of fish oil in rheumatoid arthritis. J Clin Epidemiol 1995;48(11):1379-90.

3) James MJ and Cleland LG. Dietary n-3 fatty acids and therapy for rheumatoid arthritis. Semin Arthritis Rheum 1997;27:85-97.

4) Curtis CL, Hughes CE, Flannery CR, et al. n-3 fatty acids specifically modulate catabolic factors involved in articular cartilage degradation. J Biol Chem 2000;275:721-724.

5) Geusens P et al. Long-term effect of omega-3 fatty acid supplementation in active rheumatoid arthritis. Arhtr & Rheumat 1994;37:824-829.

6) Lau CS et al. Effects of fish oil supplementation on non-steroidal anti-inflammatory drug requirement in patients with mild rheumatoid arthritis - a double-blind placebo controlled study. Br J Rheumatol 1993;32:982-989.

*These statements have not been evaluated by the Food and Drug Administration.

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