Rheumatoid arthritis patients tend to seek dietary advice from their doctors, and many undertake dietary interventions even without professional medical advice.
However, it is not known if dietary modifications are efficient against rheumatoid arthritis.
Research conducted by the Dr. Humeira Badsha Medical Center in Dubai found that certain popular diets, such as vegan, gluten-free and Mediterranean diets, were used by rheumatoid arthritis patients for intervention purposes.
Intestinal microbial modifications have been assessed for the prevention and management of rheumatoid arthritis, and that a vegan diet could benefit patients through its antioxidant constituents, lactobacilli and fibre, as well as possible changes in intestinal flora.
The review, published in The Open Rheumatology Journal, also found that the Mediterranean diet displayed anti-inflammatory effects, in part due to the presence of vitamins and omega-3 polyunsaturated fatty acids, and in part due to the gut microbiome being positively influenced.
It added that the "long-term intake of fish and other sources of long-chain polyunsaturated fatty acids are protective for development of rheumatoid arthritis".
Still, there is 'conflicting evidence' on the benefits of the Mediterranean diet on rheumatoid arthritis. Some studies have reported reduced pain and disease activity of the Mediterranean diet in rheumatoid arthritis patients, while others have found "no significant association between the adherence to (a) Mediterranean dietary pattern and the risk of rheumatoid arthritis".
At the same time, a gluten-free diet was linked to benefits for rheumatoid arthritis patients. Gluten is an immunological trigger for the condition, and a "gluten-free vegan diet for one year has been shown to significantly reduce levels of antibodies to β-lactoglobulin and gliadin, and disease activity in patients with rheumatoid arthritis".
Despite this, the review said "the existing evidence is limited".
It also covered fasting, antioxidant supplementation, flavonoids, and probiotics, but concluded that their benefits were still unclear.
However, it stated that "Vitamin D has been shown to influence autoimmunity and specifically decrease rheumatoid arthritis disease activity.
"The role of supplements such as fish oils and vitamin D should be explored in future trials to gain new insights in disease pathogenesis and develop rheumatoid arthritis-specific dietary recommendations."
The review recommended that future trials assess more specific dietary modifications, such as the link between moderate alcohol consumption, and the role of antibiotics and probiotics in rheumatoid arthritis.
It further said studies connecting rheumatoid arthritis to specific inflammation pathways and immune regulation present potential in identifying
In conclusion, it stated: "Though we tell our patients there is a limited role for diet in rheumatoid arthritis,, certain diets may help some groups of patients. However, the available evidence does not establish dietary interventions as a substitute for pharmacotherapy in rheumatoid arthritis.
"Limited or cyclical fasting, vegan (or) Mediterranean diets or elimination of dairy and gluten, all seem to play a role, but it is hard to sustain these diets long term. Dysbiosis is a key factor in rheumatoid arthritis and diet can influence the gut microbiome, and perhaps disease activity (could) be manipulated through diet and alteration of gut bacteria.
"Probiotics could have a role, although evidence for this is limited. Supplements with vitamin D, calcium, or fish oils could be useful where indicated."
Source: The Open Rheumatology Journal
"Role of Diet in Influencing Rheumatoid Arthritis Disease Activity"
Author: Humeira Badsha