title: The Role of Energy, Nutrients, Foods, and Dietary Patterns in the Development of Gestational Diabetes Mellitus: A Systematic Review of Observational Studies.
abstract: OBJECTIVE
  Diet may influence the risk of gestational diabetes mellitus (GDM), but inconsistent findings have been reported. The purpose of this study was to synthesize evidence from observational studies on the associations between dietary factors and GDM.
  
  
  METHODS
  Medline and Embase were searched for articles published until January 2015. We included observational studies of reproductive-aged women that reported on associations of maternal dietary intake before or during pregnancy, including energy, nutrients, foods, and dietary patterns, with GDM. All relevant results were extracted from each article. The number of comparable studies that adjusted for confounders was insufficient to perform a meta-analysis.
  
  
  RESULTS
  The systematic review included 34 articles comprising 21 individual studies (10 prospective cohort, 6 cross-sectional, and 5 case-control). A limited number of prospective cohort studies adjusting for confounders indicated associations with a higher risk of GDM for replacing 1-5% of energy from carbohydrates with fat and for high consumption of cholesterol (≥300 mg/day), heme iron (≥1.1 mg/day), red and processed meat (increment of 1 serving/day), and eggs (≥7 per week). A dietary pattern rich in fruit, vegetables, whole grains, and fish and low in red and processed meat, refined grains, and high-fat dairy was found to be beneficial. The current evidence is based on a limited number of studies that are heterogeneous in design, exposure, and outcome measures.
  
  
  CONCLUSIONS
  The findings support current dietary guidelines to limit consumption of foods containing saturated fat and cholesterol, such as processed meat and eggs, as part of an overall balanced diet. Further large prospective studies are warranted.
authors.affiliation: School of Public Health, University of Queensland, Brisbane, Australia d.schoenaker@uq.edu.au.
authors.forename: Danielle A J M
authors.identifier: http://orcid.org/0000-0002-7652-990X
authors.initials: DA
authors.lastname: Schoenaker
authors.affiliation: School of Public Health, University of Queensland, Brisbane, Australia.
authors.forename: Gita D
authors.identifier: http://orcid.org/0000-0001-9610-5904
authors.initials: GD
authors.lastname: Mishra
authors.affiliation: School of Medicine, University of Queensland, Brisbane, Australia Departments of Obstetric and Internal Medicine, Royal Brisbane and Women's Hospital, Brisbane, Australia.
authors.forename: Leonie K
authors.identifier: http://orcid.org/0000-0002-0137-9935
authors.initials: LK
authors.lastname: Callaway
authors.affiliation: Division of Human Nutrition, Wageningen University, Wageningen, the Netherlands.
authors.forename: Sabita S
authors.identifier: http://orcid.org/0000-0002-8830-3502
authors.initials: SS
authors.lastname: Soedamah-Muthu
mesh_terms: D002791:Cholesterol, Dietary / Q000008:administration & dosage / Q000009:adverse effects; D003430:Cross-Sectional Studies; D016640:Diabetes, Gestational / Q000453:epidemiology* / Q000209:etiology; D004032:Diet / Q000009:adverse effects; D004041:Dietary Fats / Q000008:administration & dosage* / Q000009:adverse effects; D002149:Energy Intake / Q000502:physiology*; D005247:Feeding Behavior; D005260:Female; D005638:Fruit; D006801:Humans; D008460:Meat; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D014675:Vegetables
chemical_list: D002791:Cholesterol, Dietary; D004041:Dietary Fats