Much of the research involving omega-3 fish oils in people with rheumatoid arthritis was carried out before the development of modern, disease-modifying anti-rheumatic drugs (DMARDs). These early studies showed that, in rheumatoid arthritis, taking high dose fish oil supplements (above 2.7g per day) helped to reduce pain, morning stiffness and the number of painful and tender joints. Fish oil supplements also reduced the need for non-steroidal anti-inflammatory painkillers after a delay of 2 to 3 months for the effects of the omega-3s to kick in.
Australian rheumatologists therefore investigated whether fish oils were of any benefit for people with recent-onset rheumatoid arthritis who were starting modern DMARD triple-therapy medication (methotrexate, sulphasalazine and hydroxychloroquine).
Fish oil for rheumatoid arthritis
Altogether, 140 people with rheumatoid arthritis were asked to take either 10ml high dose fish oil (5.5g EPA + DHA per day) or a control oil containing a small amount of fish oil (400mg EPA + DHA) to produce a similar ‘fishy’ odour. This ensured that neither the participants nor the doctors knew which patient was on which supplement (a double-blind, randomised, controlled trial).
After 12 months, people with rheumatoid arthritis who were taking the high dose fish oil were 76% more likely to have responded to their triple DMARD therapy (after adjusting for other factors such as smoking) than those on the control oil.
Only 10.5% of those in the high dose fish oil group ‘failed’ triple therapy and moved on to more intensive rheumatoid arthritis treatment with an immunosuppressive drug called leflunomide, compared to one-third (32.1%) of those taking the control oil.
The rate of remission in the high-dose fish oil group was double that seen in those on the control oil. A similar number (around 12%) withdrew from each group suggesting that the treatment was well tolerated.
EPA and DHA appear to work by reducing the production of immune factors that cause inflammation in the body. As well as reducing joint inflammation, omega-3 fish oils may also help to reduce the risk of heart disease in people with rheumatoid arthritis, whose risk is almost double that seen in the general population.
Fish oil supplements for rheumatoid arthritis
Omega-3 fish oil is extracted from the flesh of oily fish such as salmon, herrings, sardines, pilchards and mackerel. Their oil is a rich source of anti-inflammatory omega-3 fatty acids (EPA and DHA) which are derived from the micro-algae on which the fish feed. Studies show that a dose of at least 2.6g per day of EPA plus DHA provides the most benefit when taken in addition to standard drug treatment, with improvements in symptoms seen after around 12 weeks – it isn’t an instant effect as it takes time for the fish oils to naturally reduce the level of inflammation in the body.
Some oils are richer in EPA than DHA, and some are richer in DHA – both types of omega-3 appear to be important for optimum effects. Speak to your rheumatologist to see what dose they advise, and to check that taking fish oil will suit the medication you are on. Most experts recommend taking 3g fish oil supplements per day.
Typically, one gram of high-strength fish oil contains around 500mg of the important long-chain EPA and DHA (check label claims).
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