Diet and mental health in pregnancy: Nutrients of importance based on large observational cohort data

Objective: To determine associations between dietary intake and well-being in pregnancy. Methods: This retrospective cohort analysis combined three studies: the ROLO Study (a randomized controlled trial of a low-glycemic-index diet in pregnancy), the Pregnancy Exercise and nutrition Research Study with smartphone application support (PEARS), and a randomized controlled trial on probiotics. All data were collected before study interventions (16 wk). Dietary intakes during pregnancy were determined using 3-day food diaries. The five-item World Health Organization Well-Being Index was used to assess mental well-being. Initial associations were evaluated using Pearson correlations and further defined with multiple regression analysis adjusted for age, body mass index (BMI), Pobal Haase and Pratschke deprivation index, and metabolic equivalent of task minutes scores. Results: A total of 1521 women were included in the analysis (mean age, 32+4 y; mean BMI, 27 kg/m² [IQR, 17–56 kg/m²]). The mean well-being score was 59%. Regression analysis showed that fiber (B = 0.07; P = 0.02), magnesium (B = 0.08; P < 0.01), niacin (B = 0.09; P < 0.01), thiamine (B = 0.07; P = 0.01), and folate (B = 0.08; P = 0.02) were all positively and significantly associated with well-being in a pregnant population. The Benjamini-Hochberg procedure to correct for multiple testing was applied, and significance remained. Conclusions: Maternal nutrition and well-being are related during early pregnancy. Our findings suggest that fiber, magnesium, and particular B vitamins may be of importance for promoting positive mental well-being during pregnancy.