Managing gestational diabetes mellitus (GDM) in individuals with elevated body mass index (BMI) remains clinically challenging, particularly during late pregnancy. A randomized controlled trial published in Diabetic Medicine evaluated the feasibility, acceptability, and safety of an intermittent energy-restricted diet (ILED) compared with standard National Health Service (NHS) healthy diet and exercise advice.

The study randomized 26 women with GDM and BMI ≥27.5 kg/m² (or ≥25 kg/m² in high-risk minority ethnic groups) between 24 and 30 weeks of gestation. Participants were assigned to either an ILED regimen, which involved consuming 1000 kcal on two non-consecutive days per week along with standard care on the remaining days, or to standard care alone throughout the week. The primary outcomes included uptake, retention, and adherence to the assigned interventions, with additional assessment of maternal and neonatal safety.

The analysis showed that 73% of participants initiated their assigned intervention, and overall uptake reached 31%. Retention was 58%, and adherence to the ILED was limited, with a median completion of 37% of prescribed days. No adverse events were attributed to the intervention.

These findings indicate that intermittent energy restriction in the third trimester may be difficult to sustain in individuals with GDM, despite an acceptable safety profile.