Chrono Nutrition in Gestational Diabetes Mellitus: Implications of Meal Timing and Nutrient Distribution on Glycemic Control

Gestational diabetes mellitus (GDM), one of the most common metabolic complications of gestation, affects approximately 10–15% of pregnancies and represents a significant challenge for obstetrics and diabetologists in the attempt of reducing adverse maternal and fetal outcomes. Medical nutrition therapy remains the cornerstone of GDM management, alongside lifestyle modification and pharmacological treatment in presence of unachieved glycemic targets. However, current dietary recommendations primarily emphasize nutrient composition and caloric intake, often without fully considering the temporal aspects of food intake. Chrono-nutrition is an emerging field that investigates the interaction between meal timing, circadian rhythms, and metabolic regulation. Increasing evidence indicates that glucose metabolism and insulin sensitivity exhibit marked diurnal variations, which may be further amplified in women with GDM, resulting in time-dependent differences in postprandial glycemic responses. The narrative review summarizes current evidence on the role of chrono-nutrition in GDM by integrating mechanistic insights with findings from observational and interventional human studies. Although the available literature is limited by heterogeneity and a paucity of well-designed randomized controlled trials, the convergence of biological plausibility and emerging clinical data supports chrono-nutrition as a low-risk refinement of standard medical nutrition therapy. Incorporating temporal aspects of eating into dietary counseling may enhance glycemic management and contribute to more physiologically aligned and personalized nutritional strategies for pregnancies complicated by GDM.