Gastrointestinal tract involvement in systemic sclerosis: The roles of diet and the microbiome

•Patients with systemic sclerosis have altered gut microbial communities.•Gut microbial dysbiosis is associated with more severe gastrointestinal symptoms in SSc.•A diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols is not associated with altered gut microbiome in SSc.•Pathobiont bacterial genera are enriched in SSc patients with severe gastrointestinal symptoms.