Link Between Excessive Folate Intake and Increased Risk of Gestational Diabetes Uncovered

Recent research conducted by the University of Adelaide and Flinders University has highlighted a significant association between high maternal folate levels and the development of gestational diabetes mellitus (GDM). Although folate is essential during preconception and pregnancy to support fetal cell growth and prevent neural tube defects, new findings suggest that excessive intake—due to food fortification policies and high-dose supplementation—may raise the risk of GDM. The study analyzed over 2,000 women’s folate levels before and after fortification laws were implemented in Australia, revealing that higher maternal folate levels correlate with an increased incidence of GDM.

Current guidelines recommend daily folic acid supplementation of 400 to 500 micrograms starting at least a month prior to conception and continuing through the first trimester. However, Dr. Tanja Jankovic-Karasoulos emphasized that surplus maternal folate, resulting from both food fortification and high-dose intake, appears to contribute to the rising prevalence of GDM, which has more than tripled in Australia from 5.6% in 2010 to 19.3% in 2022.

The placenta plays a crucial role in regulating blood glucose during pregnancy, and elevated folate levels might influence placental function, potentially leading to insulin resistance. Professor Claire Roberts from Flinders University highlighted the importance of ongoing research to understand how excess folate affects maternal health and fetal development.

While adequate folate intake remains vital for preventing neural tube defects, researchers stress the need to establish safe upper limits on folic acid supplementation to mitigate the risk of gestational diabetes. Improving guidelines for folic acid use during pregnancy could safeguard both maternal and fetal health by balancing the benefits of neural defect prevention with the risks associated with high blood glucose levels.

This study underscores a critical public health issue: the importance of personalized nutrition advice during pregnancy and continuous monitoring of supplementation practices. Further investigations are necessary to refine recommendations and ensure optimal maternal and fetal health outcomes.