Nutrients that modulate gestational diabetes mellitus: A systematic review of cohort studies Jan 2019-Jan 2020.

BackgroundThe role of eating habits of pregnant women in the development and treatment of gestational diabetes mellitus (GDM) is well established.ObjectivesTo estimate the contribution of specific nutrients and dietary patterns in the development or privation of GDM in pregnant women.Data sourcesA systematic review of cohort studies, published between January 2019 and January 2020, of English articles using PubMed, Scopus and Europe PMC databases. Search terms included diabetes, pregnancy, dietary, food, and nutrients.Study selectionOnly cohort studies about the association between eating habits before and during pregnancy and the risk of GDM in English were included. The studies used dietary patterns, specific nutrients or records of food intake of the participants using a questionnaire.Data extractionTwo authors independently extracted data from articles-including dietary patterns, food intake, nutrients, number and demographic data of participants, data about pregnancies-using predefined criteria.ResultsIn total, 28 cohort studies were organised to examine the correlation between dietary patterns and the prevention of GDM. Studies were conducted in 13 countries and included 3 058 242 participants. Of those, 13 (46%) studies focused on the consumption of vitamins, probiotics, micronutrients, folate, vegetables and fruits. Moreover, seven (25%) studies focused on what is considered to be "unhealthy" eating habits, including prudent and Western dietary patterns. The mediterranean pattern was used in three (11%) studies.ConclusionsOngoing studies support advice to adhere to a healthy balanced diet, with the addition of folic acid and a multi-vitamin suitable for pregnancy. There is new evidence suggesting probiotics and cod-liver oil supplementation may improve glycaemic control and also the important consideration of the psychological influences of eating.