The Effect of the Ideal Food Pyramid on Gut Microbiota in Rheumatoid Arthritis Patients

Background: Rheumatoid arthritis (RA) is a dysbiosis of the gut microbiota, and diet is one of the powerful environmental factors that can alter the microbiota. The aim of the clinical study was to determine the effect of the Ideal Food Pyramid on gut microbiota in RA patients; as well as its effect on disease activity, biochemical findings and anthropometric measurements. Methods: Thirty patients diagnosed with RA who met the inclusion criteria were randomly divided into diet and control groups and followed for 12 weeks. Gut microbiota composition was determined by 16S rRNA gene sequencing. Results: At the end of the study, Simpson, Shannon and Chao-1 indices were higher in the diet group (16) than in the control group (14), although not significantly (p>0.05). At the phylum level, the relative abundance of Firmicutes increased and the abundance of Bacteroidetes decreased in the diet group at the end of the trial. At species level, Prevotella Copri, Bacteroides fragilis, Prevotella stercorea, Bacteroides uniformis decreased while Faecalibacterium prausnitzii, Roseburia faecis, Bacteroides ovatus, Akkermansia muciniphila, Coprococcus eutactus, Gemmiger formicilis, Ruminococcus bromii, Bifidobacterium longum species increased in the diet group. Conclusion: The Ideal Food Pyramid has been determined to have many clinical benefits for RA patients, especially for the gut microbiota.