Ultra-processed Foods and Diet Quality in Association With Long-term Weight Change and Progression to Type 2 Diabetes Among Individuals With a History of Gestational Diabetes Mellitus-A Prospective Study.

Objective: We examined the associations of overall and group-specific ultra-processed food (UPF) consumption with long-term weight change and type 2 diabetes (T2D) progression following gestational diabetes mellitus (GDM)-complicated pregnancies.

Research Design And Methods: We included 4,207 women with a history of GDM from the Nurses' Health Study II (1991-2021). UPF intake (servings/day) was assessed via food frequency questionnaires every 4 years and quantified per the NOVA classification. Diet quality was evaluated using the Alternate Healthy Eating Index-2010 (AHEI). Associations between UPF intake changes and weight changes (kg) were assessed using generalized estimating equations (GEE) (n = 3,781). Cox regression models estimated adjusted hazard ratios (HRs) and 95% CIs of habitual UPF intake modeled by time-updated cumulative averages with T2D risk. Joint associations of UPF and AHEI with weight change and T2D risk were examined using the same GEE and Cox regression models, respectively.

Results: T2D developed in 1,040 participants. Increased UPF consumption was associated with greater weight gain (P-trend < 0.0001; quartile [Q]1 vs. Q4: 0.52 kg vs. 1.65 kg). Habitual UPF consumption was positively associated with T2D risk: adjusted HRs (95% CIs) for Q1 to Q4 were 1.00 (ref), 1.07 (0.87, 1.32), 1.25 (1.03, 1.53), and 1.20 (0.99, 1.46), respectively (P-trend = 0.04). These associations persisted in women with higher AHEI scores. When modeling UPF and AHEI jointly, only women with stable or decreased UPF intake and increased AHEI achieved 4-year weight maintenance.

Conclusions: In women with a history of GDM, UPF consumption was associated with weight gain and higher T2D risk, even among those with higher diet quality.