Diet during pregnancy and disparities in fetal growth: the NEST cohort

Abstract

Diet in pregnancy is thought to potentially contribute to race/ethnic disparities in reproductive outcomes, but evidence is scarce. We assessed how Mediterranean diet (MD) adherence and “junk foods” (e.g. cakes/pastries) related to fetal growth among 788 women from the Newborn Epigenetic Study (NEST) using food frequency data. MD scores were based on intakes >median for 8 beneficial (fruit, vegetables, fish, dairy products, whole grains, nuts, legumes, mono:saturated fat) and <median for 2 less beneficial (processed and unprocessed meats) items. Compared with white women (mean birthweight [BW] 3391g), education‐adjusted differences in BW were ‐220±40g in Blacks. MD scores were lower in Black than white women, while junk food intakes were higher (P<0.05). In BW models, pre‐pregnancy BMI by MD adherence interactions were significant (P<0.10). High MD adherence (>7 points) was associated with increased BW in normal weight women (P<0.05), with benefits of this diet attenuated in overweight women. Associations between BW and/or low BW with MD components such as whole grains were positive, while associations with cakes/pastries were negative. However, adjusting for MD score or food groups only slightly attenuated race disparities in BW. Results highlight disparities in intake that may influence fetal growth, but suggest the role of diet in BW disparities is complex.