Social and Economic Patterning in Ultra-Processed Food Intake in Toddlerhood and Middle Childhood: Longitudinal Data From the Gemini Cohort in the United Kingdom.

Abstract

Background: Children's consumption of ultra-processed food (UPF) may contribute to inequalities in obesity and wider health. Socioeconomic patterning in younger UK children's UPF intake is unknown.

Objective: The aim of this study was to investigate socioeconomic patterning of UK toddlers' (aged 21 months) and children's (aged 7 years) UPF intake across several household and neighborhood indicators.

Design: Secondary analysis of data from a prospective longitudinal cohort study using parent-reported sociodemographic data and 3-day diet diaries.

Participants/setting: Participants were children from the UK Gemini study of 4804 twins born in 2007. At ages 21 months and 7 years, 2591 and 592 children, respectively, had at least 2 days of dietary data.

Main outcome measures: This study measured percentage energy from UPF at 21 months and 7 years of age, classified using the NOVA system.

Statistical analyses performed: Unadjusted linear regression models were run for household socioeconomic position (SEP) composite score; index of multiple deprivation decile; income; occupation level; mother's age; education of mother and partner; and child's ethnicity, sex, and age. Adjusted multivariable linear regression models were adjusted for ethnicity and all SEP indicators except SEP composite score (adjusted 1), in addition to child sex and age (adjusted 2). Missing data were addressed with multiple imputation and inverse probability weighting. CIs and P values were adjusted to account for clustering within families.

Results: Children of lower SEP had higher UPF intake across several indicators. Mother's education was the strongest predictor; postgraduate education was associated with 8.64% (95% CI -12.08% to -5.20%; P < .001) and 10.12% (95% CI, -15.68% to -4.56%; P < .001) less energy from UPF at 21 months and 7 years, respectively, compared with no educational qualifications in adjusted model 2.

Conclusions: UK children from more disadvantaged backgrounds consumed a greater proportion of their energy from UPF. Mother's education seemed to be the most influential factor. Socioeconomic inequalities, particularly in maternal education, may drive disparities in diet quality and associated health outcomes. Addressing these gaps is essential to reduce childhood obesity and improve long-term health in socioeconomically disadvantaged populations.