(P02-050-23) Age and Time Trends in Greenhouse Gas Emissions and Land Use of Diets Among Children and Adolescents of the German DONALD Cohort Study

Objectives: Environmental impact of human diets is highly relevant for planetary health. As relevant age group for establishing nutritional behaviour and as the future generation children and adolescents are of great research interest in this debate. Therefore, our aim was to analyse age and time trends of Greenhouse Gas Emission (GHGE) and Land Use (LU) of diets in children and adolescents in Germany, and additionally confirm associations with animal and plant protein intake as decisive nutritional variables.

Methods: A total of 5,511 3-day-weighted dietary records, conducted between 2000 and 2021 by 856 participants (6-17y) of the dynamic DONALD cohort study (DOrtmund Nutritional and Anthropometric Longitudinally Designed) were analysed. All reported food items were linked to the SHARP indicator database, which contained GHGE (kgCO²eq) and LU (m² x year) per kg of each food item determined by life-cycle analysis. Multivariable adjusted polynomial mixed‑effects regression models were used to identify time and age trends of GHGE and LU (per day and per 1000 kcal) as well as to examine associations with the ratio of animal to plant protein and GHGE and LU per 1000 kcal.

Results: Overall, total daily energy intake was a main driver for dietary GHGE and LU. However, GHGE/1000kcal and LU/1000kcal increased slightly with age (p≤0.0198). With regard to time trends, GHGE/1000kcal and LU/1000kcal slightly increased between 2000 and 2010 and slightly decreased thereafter (p≤0.0048) among girls. No significant time trend was found for boys (p >0.05). A higher ratio of animal to plant protein was directly associated with GHGE/1000kcal (ß=0.40, 95%CI: 0.35-0.44, p< 0.0001) and LU/1000kcal (ß=0.52, 95%CI: 0.43-0.61, p< 0.0001).

Conclusions: The ratio of animal to plant protein was confirmed to be an indicator for an environmentally sustainable diet. Also standardized for energy intake as a main predictor of GHGE and LU, adolescents’ dietary practices appear to be less favourable than those of younger children with regard to GHGE and LU. The only small decrease in dietary GHGE and LU in recent years, and only among girls, underscores the need for systemic changes.

Funding Sources: The DONALD study is financially supported by the Ministry of Science and Research of North Rhine-Westphalia, Germany. The project is financed by the German Research Foundation.