The fish oil (FO) story began when a young Danish doctor noticed that there were no heart attacks in Greenland. Large epidemiological studies were initiated, mechanistic investigations followed, and a huge amount of fascinating data emerged. Today, we know more about FO than most other dietary supplements.
Fish oil contains large amounts of omega-3 fatty acids which are thought to be beneficial in treating hypertriglyceridemia, preventing heart disease. In addition, FO is often recommended for a wide variety of other conditions, such as cancer, depression, and macular degeneration. Perhaps the most compelling evidence exists in the realm of inflammatory diseases; the mechanism of action of FO is well-studied and includes powerful anti-inflammatory properties.
Australian rheumatologists just published a study of FO supplements for patients suffering from rheumatoid arthritis (RA). Specifically, they examined the effects of high versus low dose FO in early RA employing a ‘treat-to-target’ protocol of combination disease-modifying anti-rheumatic drugs (DMARDs).
Patients with chronic RA <12 months’ who were DMARD-naïve were enrolled and randomised 2:1 to FO at a high dose or plaacebo (low dose FO for masking). These groups were given 5.5 or 0.4 g/day, respectively, of eicosapentaenoic acid + docosahexaenoic acid. All patients received methotrexate (MTX), sulphasalazine and hydroxychloroquine, and DMARD doses were adjusted according to an algorithm taking disease activity and toxicity into account. DAS28-erythrocyte sedimentation rate, modified Health Assessment Questionnaire (mHAQ) and remission were assessed three monthly. The primary outcome measure was failure of triple DMARD therapy.
The results indicate that, the FO group, failure of triple DMARD therapy was lower (HR=0.28 (95% CI 0.12 to 0.63; p=0.002) unadjusted and 0.24 (95% CI 0.10 to 0.54; p=0.0006) following adjustment for smoking history, shared epitope and baseline anti–cyclic citrullinated peptide. The rate of first American College of Rheumatology (ACR) remission was significantly greater in the FO compared with the control group (HRs=2.17 (95% CI 1.07 to 4.42; p=0.03) unadjusted and 2.09 (95% CI 1.02 to 4.30; p=0.04) adjusted). There were no differences between groups in MTX dose, DAS28 or mHAQ scores, or adverse events.
The authors conclude that FO was associated with benefits additional to those achieved by combination ‘treat-to-target’ DMARDs with similar MTX use. These included reduced triple DMARD failure and a higher rate of ACR remission.
These findings are most encouraging, particularly as they collaborate those of systematic reviews which concluded that evidence is seen for a fairly consistent, but modest, benefit of marine n-3 PUFAs on joint swelling and pain, duration of morning stiffness, global assessments of pain and disease activity, and use of non-steroidal anti-inflammatory drugs and …there is evidence from 6 of 14 randomized controlled trials supporting a favourable effect of n-3 LCP supplementation in decreasing joint inflammation in RA. And you don’t need to buy the supplements either; regularly eating lots of fatty fish like mackerel, sardine or salmon has the same effects.
So, here we have an alternative, ‘natural’, dietary supplement or diet that is supported by reasonably sound evidence for efficacy, that has very few adverse effects (the main one being contamination of the supplement with toxins), that generates a host of potentially useful effects on other organ systems, that is affordable, that has a plausible mechanism of action…. Hold on, I hear some people interrupting me, FO is not an alternative medicine, it is mainstream! Exactly, an alternative medicine that works is called….MEDICINE.