Diet and Gestational Diabetes Mellitus: A Systematic Review Study

Objective: Diet may have an impact on gestational diabetes mellitus (GDM) development; nevertheless, controvertible studies have been published. The aim of this study was to provide evidence from analytical studies on the relationship between diet and GDM development. Methods: Following the PRISMA guidelines, ISI Web of Knowledge, PubMed, Google Scholar, Scopus, Embase, and the Cochrane library were searched for articles published in the English language from Jan 2005 to Dec 2020. We included observational studies, assessed their risk of bias, and extracted data on association between diet status and GDM development. Keywords were selected based on the Mesh terms, which included gestational diabetes mellitus“, “GDM”, “diet,” “nutrition,” “food,” “dietary pattern which was combined by "OR" and "AND" Boolean operators. Two reviewers (SHA and PM) independently reviewed abstracts and full-text articles and extracted data. Results: Among the 5 articles included, 4 were case-control and one was a cross-sectional study. Studies have shown that diets with a high intake of saturated fatty acids (more than 10% of total daily fat intake) and trans fatty acids (more than 1% of total daily fat intake) before and during pregnancy significantly increase the risk of gestational diabetes mellitus. Conclusion: High intake of saturated fat and trans fat before and during pregnancy can disturb glucose metabolism and increase the risk of GDM, although all of the studies recommend more widespread observational and clinical trials studies to identify the exact relationship between high saturated and trans fatty acids intake and GDM.