{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T07:38:47Z","timestamp":1770709127771,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Type 1 diabetes (T1D) is characterized by autoimmune beta-cell destruction and lifelong insulin dependence, yet early-stage disease (Stages 1\u20132) retains residual beta-cell function that may still respond to incretin signaling. Incretin hormones\u2014mainly glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP)\u2014enhance postprandial insulin secretion and suppress glucagon, and GLP-1 also exhibits beta-cell protective effects in preclinical models. Although the incretin effect is markedly reduced in established T1D, intestinal GLP-1 secretion is largely preserved, creating a mechanistic rationale for strategies that increase endogenous GLP-1 during the \u201cresidual function\u201d window. This narrative review summarizes dietary and lifestyle interventions that may enhance endogenous GLP-1 responses and discusses their potential role as adjuncts to insulin therapy, particularly when combined with emerging beta-cell-preserving immunomodulatory approaches that may prolong early disease stages. Mechanistically, high-fiber diets may increase GLP-1 via microbiota-derived short-chain fatty acids acting on L-cell receptors; low-glycemic index carbohydrates may favor distal nutrient delivery and a GLP-1-dominant incretin profile; and Mediterranean dietary patterns may promote GLP-1 secretion through unsaturated fatty acids, fiber, and polyphenols, including potential DPP-4-modulating effects. This narrative review examines nutrition and lifestyle interventions modulating residual incretins to elongate early T1D stages and enhance glycemic control as insulin adjuncts, per Nutrients\u2019 Special Issue. Available evidence is strongest in non-T1D populations, with limited T1D-specific trials, highlighting the need for stage-targeted studies incorporating GLP-1 dynamics, C-peptide, glycemic variability, and microbiome outcomes.<\/jats:p>","DOI":"10.3390\/nu18040564","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T12:42:42Z","timestamp":1770640962000},"page":"564","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Nutritional Interventions in Type 1 Diabetes: Boosting Residual GLP-1 Responses\u2014Is It an Option?"],"prefix":"10.3390","volume":"18","author":[{"given":"Maria","family":"Grammatiki","sequence":"first","affiliation":[{"name":"Division of Endocrinology and Metabolism and Diabetes Center, First Department of Internal Medicine, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, 54636 Thessaloniki, PC, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1879-856X","authenticated-orcid":false,"given":"Xanthippi","family":"Tsekmekidou","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Metabolism and Diabetes Center, First Department of Internal Medicine, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, 54636 Thessaloniki, PC, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5853-1352","authenticated-orcid":false,"given":"Theocharis","family":"Koufakis","sequence":"additional","affiliation":[{"name":"Second Propedeutic Department of Internal Medicine, Hippokration Hospital, School of Medicine, Aristotle University of Thessaloniki, 54636 Thessaloniki, PC, Greece; <email>thkoyfak@auth.gr<\/email>"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2376-740X","authenticated-orcid":false,"given":"Kalliopi","family":"Kotsa","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Metabolism and Diabetes Center, First Department of Internal Medicine, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, 54636 Thessaloniki, PC, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"170183","DOI":"10.1016\/j.peptides.2019.170183","article-title":"Evaluation of the incretin effect in humans using GIP and GLP-1 receptor antagonists","volume":"125","author":"Gasbjerg","year":"2020","journal-title":"Peptides"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/j.drudis.2011.08.017","article-title":"The potential of incretin-based therapies in type 1 diabetes","volume":"17","author":"Suen","year":"2012","journal-title":"Drug Discov. 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