Childhood obesity is a significant public health concern in Europe, with long-lasting health consequences. Dietary habits are shifting towards highly processed foods, impacting dietary quality and increasing obesity risk. This study aimed to identify dietary patterns in children across various European countries and assess their prospective association with adiposity-related outcomes. The researchers utilized both data-driven and a priori methods to analyze dietary patterns, acknowledging the limitations of each approach. The study sought to address the lack of research on data-driven dietary patterns in children across different European countries and their association with adiposity.

Existing literature highlights the high prevalence of overweight and obesity among school-aged children in Europe and the long-term health implications of childhood obesity. Studies indicate a strong link between dietary intake and obesity, with a shift from traditional diets, such as the Mediterranean diet, towards highly processed diets. While previous research has examined dietary patterns and their relation to obesity, this study aimed to derive data-driven dietary patterns in a multi-country setting to understand the variations and impacts across different populations.

This study utilized data from six European birth cohorts within the Human Early-Life Exposome (HELIX) project, including participants from Spain, France, UK, Greece, Lithuania, and Norway. Dietary data were collected via parent-reported semi-quantitative food frequency questionnaires (FFQs) when children were aged 6-11 years (childhood) and again in adolescence (12-18 years). Exploratory factor analysis (EFA) was used to derive data-driven dietary patterns from the FFQ data. The Mediterranean KIDMED index was also calculated to assess adherence to the Mediterranean diet. Adiposity-related outcomes, including BMI z-score (zBMI), fat mass proportion, and waist-to-height ratio, were measured at both visits. Generalized linear regressions, adjusted for confounders (cohort, age, sex, maternal pre-pregnancy BMI, maternal smoking, maternal education, family affluence, and child sedentary behavior), were used to analyze associations between dietary patterns and adiposity. Inverse probability weighting was used in the adolescent analysis to address potential selection bias due to follow-up loss. The study followed ethical guidelines, with informed consent obtained from all participants.

Five data-driven dietary patterns were identified: 'Meat', 'Dairy', 'Western', 'Healthy', and 'Sweets and fats'. Norwegian children showed the highest adherence to the 'Healthy pattern' (high intake of fruits, vegetables, and fish), while Lithuanian children had the highest adherence to the 'Western pattern' (high consumption of sweets, beverages, potatoes, and bakery products). Children with low adherence to the 'Healthy pattern' had higher fat mass proportions in childhood and higher zBMI and waist-to-height ratios in adolescence. Low adherence to the 'Dairy pattern' was associated with lower zBMI and fat mass in childhood, but not in adolescence. No significant associations were observed with the KIDMED index.

The study's findings highlight the considerable variation in dietary patterns across European countries, emphasizing the need for country-specific interventions. The inverse association between adherence to a 'Healthy pattern' and adiposity-related outcomes supports the importance of promoting fruit, vegetable, and fish consumption in children. The unexpected negative association between low 'Dairy pattern' adherence and childhood adiposity requires further investigation, potentially considering factors like the type of dairy products consumed. The lack of association with the KIDMED index might be due to the limited sensitivity of the index in capturing the complexities of dietary patterns or variations across different countries. The findings contribute to the understanding of the diverse dietary patterns among European children and their relationship with adiposity.

This study demonstrates that many European children have poor diets and that low adherence to a healthy dietary pattern is associated with adiposity-related outcomes. Assessment of children's dietary patterns is essential for tailoring dietary advice and supporting families in preventing excess weight gain. Future research should investigate the long-term effects of these dietary patterns, explore the influence of specific food items within patterns, and consider the impact of socio-economic factors on dietary choices and access to healthy foods.

The use of parent-reported FFQs may lead to reporting bias, particularly underreporting of unhealthy foods. The study's focus on food groups, rather than individual food items, may limit the detailed understanding of specific nutrient contributions. The relatively small sample size and high country variance may influence the generalizability of the findings. The study did not account for school meals or energy intake in calories. Lastly, the high representation of children from higher socioeconomic backgrounds may limit generalizability to more diverse populations.