Associations between prenatal (poly)phenol intake and cognitive outcomes in school-age children

Background: (Poly)phenol intake is associated with improved cognitive function in adults, with emerging evidence suggesting benefits in children. However, the role of prenatal (poly)phenol exposures in cognitive development remains a gap in early-life nutrition research. Objective: This analysis of a longitudinal cohort tested the associations between prenatal (poly)phenol intakes and cognitive outcomes in school-age children at age 5 and 8 years. Methods: Participants included mother-child pairs enrolled in a prospective, longitudinal study during pregnancy and completed 5- and 8-year follow-up visits (N = 129). 3-day food records were used to estimate prenatal and child intakes of energy and 18 (poly)phenol subclasses using a database developed from Phenol-Explorer (v3.6). The analytical sample included children (N = 111) with completed assessments for academic achievement, language skills, and intelligence quotient (IQ) scores (Mean = 100, SD = 15). Regression models estimated associations between (poly)phenol intakes and cognitive outcomes, adjusted for breastfeeding duration, maternal IQ, pre-pregnancy BMI, gestational age, and infant sex. Results: Average prenatal total (poly)phenol intake was 716 mg/d. Prenatal (poly)phenol intakes were not associated with child academic achievement scores. Higher prenatal flavone intakes were associated with higher language ({beta}: 4.36, p = 0.045) and IQ ({beta}: 9.43, p = 0.002) scores. Higher flavonol ({beta}: -4.67, p = 0.022) or hydroxybenzoic acid intakes ({beta}: -3.88, p = 0.026) were associated with lower language scores. Major sources of flavones and lignans included coffee, orange juice, and herbal tea. Coffee, cranberry, black tea, okra, and tomato sauce provided flavonols and hydroxybenzoic acids. Conclusions: Associations between prenatal (poly)phenol intake and child cognitive outcomes were mixed and differed by subclass. Further investigation is needed to explore the role of co-occurring nutrients and other dietary components. These findings suggest that (poly)phenol subclasses derived from healthier plant-based foods, including citrus fruit and herbal tea, may associate with improved child cognitive outcomes.