Changes in the gut microbiomes of healthy volunteers who followed a gluten-free diet (GFD) for four weeks were studied. Per participant, nine stool samples were collected: one at baseline, four during the GFD period, and four when they returned to their habitual diet. Microbiome profiles were determined using 16S rRNA sequencing and the samples were next processed for taxonomic and imputed functional composition. Additionally, participants kept a 3-day food diary and six gut health-related biomarkers were measured.