Dietary index for gut microbiota and odds of gestational diabetes mellitus: associations with inflammatory and metabolic biomarkers.

Background: Gestational diabetes mellitus (GDM) is a common metabolic disorder of pregnancy associated with adverse maternal and neonatal outcomes. Emerging evidence suggests that dietary patterns supportive of gut microbial health and associated systemic inflammation may contribute to the pathophysiology of GDM. This study evaluated the association between a dietary index oriented toward gut microbiota (DI-GM)-comprising foods previously linked to beneficial gut microbial composition-and GDM odds, metabolic profiles, inflammatory markers, and pregnancy outcomes. Methods: This case-control study included 800 pregnant women (400 GDM cases and 400 controls) at 24-28 weeks of gestation. Dietary intake was assessed using a validated food frequency questionnaire, and DI-GM scores were derived based on intake of microbiota-supportive and disruptive foods. Biochemical measurements included glucose parameters, lipid profile, hs-CRP, IL-6, TNF- Results: Women with GDM had lower DI-GM scores than controls (7.09 ± 1.64 vs. 9.52 ± 1.83, Conclusion: Greater adherence to a microbiota-oriented dietary pattern was associated with lower GDM odds and improved maternal-neonatal outcomes. However, without direct gut microbiota measurement, these findings represent associations-not confirmation-of diet-microbiota-inflammation pathways, and require further investigation.