Association of maternal ultra-processed food consumption during pregnancy with atopic dermatitis in infancy: Korean Mothers and Children's Environmental Health (MOCEH) study.

Background: Maternal diet during pregnancy might influence the development of childhood allergic disorders. There are few studies on the association between processed food intake and infant atopic dermatitis (AD) during pregnancy. The aim of the present study was to investigate the association of ultra-processed food (UPF) intake during pregnancy with infantile AD.

Methods: This study involved 861 pairs of pregnant women and their offspring from the Mothers' and Children's Environmental Health (MOCEH) study, a multi-center birth cohort project conducted in Korea. Dietary intake was estimated using a 24-h recall method at 12-28 weeks gestation. The NOVA classification was used to identify UPF, and UPF intake was calculated as the percentage of total energy consumption and categorized into quartiles. Infantile AD was assessed based on medical history and the criteria of the International Study of Asthma and Allergies in Childhood (ISAAC). Associations were assessed by logistic regression with adjustment for confounding factors.

Results: Children born to mothers in the highest quartile of UPF consumption (15.5% or more of the total energy) compared to the lowest quartile (6.8% or less) showed a higher risk of AD within 12 months [odds ratio (OR) = 1.69; 95% confidence interval (CI): 1.07-2.66, P for trend 0.0436]. After adjustment for the confounding factors under study, the association was strengthened; the adjusted OR between extreme quartiles was 2.19 (95% CI: 1.11-4.32, P for trend = 0.0418). This association was maintained even after an additional adjustment based on the Korean Healthy Eating Index (KHEI), an indicator of diet quality.

Conclusions: Higher maternal consumption of UPF during pregnancy was associated with a greater risk of infantile AD within the first year of life.