Diet therapy in rheumatoid arthritis: A review of the evidence

Rheumatoid arthritis (RA) is a chronic rheumatic disease characterised by progressive joint damage and extra-articular manifestations that can lead to disability. The aetiology of autoimmune diseases, including RA, is complex, involving genetic, hormonal, dietary, and environmental factors. However, the physiological mechanisms by which these agents contribute to pathogenesis have not yet been fully defined. More recent studies suggest an impact of gut microbiome dysbiosis on the pathogenesis of autoimmune diseases in both animal and human models, including rheumatoid arthritis, also suggesting altered intestinal permeability as a possible cause. This modification of the gut microbiome may be related to influential diet patterns in the prevention of this pathology, as well as a proposed complementary treatment to traditional pharmacological treatment, also considering the increased risk for these patients of developing metabolic syndrome and "rheumatoid cachexia", an accumulation of adipose tissue accompanied by a decrease in muscle tissue due to catabolic changes due to chronic inflammation and physical inactivity as a consequence of motor difficulties in RA. With the emergence of recent evidence proposing dietary interventions and eating patterns as adjunctive treatment to drug therapy in the management of RA, the following narrative qualitative review proposes reviewing recent evidence on the effectiveness of various proposed dietary interventions in the treatment of rheumatoid arthritis in terms of pain and disease activity, finding between a high heterogeneity of proposed interventions, those dietary patterns with modulating effect on the gut microbiome as Mediterranean diet and its variations in the context of promoting a healthy lifestyle would be positive as a complementary therapy for this disease.