Associations Between Maternal Pre-Pregnancy Dietary Patterns and Body Composition in Preschool Children: A...

Maternal nutritional status before pregnancy may influence offspring long-term health; however, the association between pre-pregnancy dietary patterns and body composition in preschool children remains unclear.

This study used data from the Taicang and Wuqiang Mother-Child Cohort Study (TAWS), comprising 582 mother-child pairs. Dietary intake during the month before pregnancy was assessed using a food frequency questionnaire. Dietary patterns were derived via principal component analysis. Standardized pattern scores (mean = 0, SD = 1) were analyzed as continuous variables (per 1-SD increase) and categorized into quartiles (Q1-Q4, with Q1 as reference). Body composition indicators (percent body fat [PBF], fat mass index [FMI], fat-free mass index [FFMI], and skeletal muscle index [SMI]) were measured by bioelectrical impedance analysis in children aged 3-6 years. Multiple linear regression was used to examine associations under two models: an unadjusted model and a multivariable model adjusted for child characteristics, maternal sociodemographic and gestational factors, family factors, feeding mode, and other dietary patterns. Interaction terms were introduced to test for potential effect modification by child sex and maternal pre-pregnancy BMI.

Results showed that five maternal pre-pregnancy dietary patterns were extracted: animal-based food, grain-vegetable-fruit, processed meat-dairy, vegetable-legume, and cured vegetable. In multivariable-adjusted models, the processed meat-dairy pattern was positively associated with FMI (Q4 vs. Q1: β = 0.262, 95% CI: 0.036 to 0.488). The grain-vegetable-fruit pattern was inversely associated with FFMI (Q4: β = -0.265, 95% CI: -0.510 to -0.020) and SMI (Q4: β = -0.256, 95% CI: -0.564 to -0.113). The vegetable-legume pattern was associated with higher PBF (Q3: β = 0.234, 95% CI: 0.007 to 0.461) and lower SMI (Q4: β = -0.338, 95% CI: -0.564 to -0.113). No significant associations were observed for the animal-based food or cured vegetable pattern after adjustment. Sex-stratified analyses showed that the animal-based food pattern was associated with FFMI and SMI in opposite directions between boys and girls (p for interaction = 0.048 and 0.013, respectively). Maternal pre-pregnancy BMI significantly modified only the association between the processed meat-dairy pattern and SMI (p for interaction = 0.032).

Maternal pre-pregnancy dietary patterns were selectively associated with body composition in preschool children: the processed meat-dairy pattern was associated with higher fat mass, while the grain-vegetable-fruit and vegetable-legume patterns were associated with lower muscle indices. These associations are observational in nature and do not imply causality. In particular, the associations of plant-based dietary patterns with muscle indices should be interpreted with caution and should not be regarded as negative effects of plant-based diets.