Adherence to plant-based diet during pregnancy and risk of gestational diabetes: a prospective birth cohort study

Studies have shown that plant-based foods have a protective effect against gestational diabetes (GDM). We examined the association between plant-based dietary patterns and the risk of GDM in a sample of Iranian adults.

We enrolled 635 pregnant women for the present study. Dietary intakes were evaluated by using a 90-item food frequency questionnaire during the first trimester of pregnancy. Three plant-based including plant-based (PDI), unhealthy (uPDI) and healthy (hPDI) were calculated. Cox proportional hazard model were fitted to estimate hazard ratio (HR) and 95% confidence interval (CI) of GDM across categories of the plan-based dietary indices, while controlling for age, educational level, physical activity, family income, prepregnancy body mass index, gestational weight gain, and total energy intake.

A total of 635 mothers were included, of whom 79 participants were diagnosed with GDM. Those in the third tertile of the PDI (HR: 0.55, 95% CI: 0.30, 0.98) and hPDI (HR: 0.43, 95% CI: 0.24, 0.78) had a lower risk of developing GDM during their current pregnancy as compared to the first tertile. There was no association between uPDI and risk of GDM.

We found that higher adherence to a plant-based diet during early pregnancy may be associated with a lower GDM risk among Iranian women. Confirmation of this finding is necessary in larger cohort studies, taking into account other pregnancy outcomes such as birth weight.