{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T19:49:20Z","timestamp":1790624960745,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,7,22]],"date-time":"2025-07-22T00:00:00Z","timestamp":1753142400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Agence Nationale de la Recherche","award":["Gluthealth"],"award-info":[{"award-number":["Gluthealth"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background\/Objectives: An increasing number of apparently healthy individuals are adhering to a gluten-free lifestyle without any underlying medical indications, although the evidence for the health benefits in these individuals remains unclear. Although it has already been shown that a low- or gluten-free diet alters the gut microbiota, few studies have examined the effects of this diet on healthy subjects. Therefore, our aim was to evaluate whether and how a prolonged low-gluten diet impacts gut microbiota composition and function in healthy adults, bearing in mind its intimate link to the host\u2019s health. Methods: Forty healthy volunteers habitually consuming a gluten-containing diet (HGD, high-gluten diet) were included in a randomised control trial consisting of two successive 8-week dietary intervention periods on a low-gluten diet (LGD). After each 8-week period, gut microbiota composition was assessed by 16S rRNA gene sequencing, molecular quantification by qPCR, and a cultural approach, while its metabolic capacity was evaluated through measuring faecal fermentative metabolites by 1H NMR. Results: A prolonged period of LGD for 16 weeks reduced gut microbiota richness and decreased the relative abundance of bacterial species with previously reported potential health benefits such as Akkermansia muciniphila and Bifidobacterium sp. A decrease in certain plant cell wall polysaccharide-degrading species was also observed. While there was no major modification affecting the main short-chain fatty acid profiles, the concentration of the intermediate metabolite, ethanol, was increased in faecal samples. Conclusions: A 16-week LGD significantly altered both composition and metabolic production of the gut microbiota in healthy individuals, towards a more dysbiotic profile previously linked to adverse effects on the host\u2019s health. Therefore, the evaluation of longer-term LDG would consolidate these results and enable a more in-depth examination of its impact on the host\u2019s physiology, immunity, and metabolism.<\/jats:p>","DOI":"10.3390\/nu17152389","type":"journal-article","created":{"date-parts":[[2025,7,22]],"date-time":"2025-07-22T11:44:45Z","timestamp":1753184685000},"page":"2389","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Low-Gluten Diet Reduces the Abundance of Potentially Beneficial Bacteria in Healthy Adult Gut Microbiota"],"prefix":"10.3390","volume":"17","author":[{"given":"Eve","family":"Delmas","sequence":"first","affiliation":[{"name":"UMR454 MEDIS, Universit\u00e9 Clermont Auvergne\/INRAE, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7782-7538","authenticated-orcid":false,"given":"Rea","family":"Bingula","sequence":"additional","affiliation":[{"name":"UMR 1019 Nutrition Humaine, Universit\u00e9 Clermont Auvergne\/INRAE, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christophe","family":"Del\u2019homme","sequence":"additional","affiliation":[{"name":"UMR454 MEDIS, Universit\u00e9 Clermont Auvergne\/INRAE, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3477-4904","authenticated-orcid":false,"given":"Nathalie","family":"Meunier","sequence":"additional","affiliation":[{"name":"CRNH Auvergne, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aur\u00e9lie","family":"Caille","sequence":"additional","affiliation":[{"name":"CRNH Auvergne, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"No\u00eblle","family":"Lyon-Belgy","sequence":"additional","affiliation":[{"name":"CRNH Auvergne, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9061-2953","authenticated-orcid":false,"given":"Ruddy","family":"Richard","sequence":"additional","affiliation":[{"name":"CRNH Auvergne, CHU Clermont-Ferrand, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Gloria","family":"Do Couto","sequence":"additional","affiliation":[{"name":"UMR454 MEDIS, Universit\u00e9 Clermont Auvergne\/INRAE, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3811-8859","authenticated-orcid":false,"given":"Yohann","family":"Wittrant","sequence":"additional","affiliation":[{"name":"UMR 1019 Nutrition Humaine, Universit\u00e9 Clermont Auvergne\/INRAE, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7541-4417","authenticated-orcid":false,"given":"Annick","family":"Bernalier-Donadille","sequence":"additional","affiliation":[{"name":"UMR454 MEDIS, Universit\u00e9 Clermont Auvergne\/INRAE, 63000 Clermont-Ferrand, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hansen, L.B.S., Roager, H.M., S\u00f8ndertoft, N.B., G\u00f8bel, R.J., Kristensen, M., Vall\u00e8s-Colomer, M., Vieira-Silva, S., Ibr\u00fcgger, S., Lind, M.V., and M\u00e6rkedahl, R.B. 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