Deriving Sustainable Food-Based Dietary Guidelines for Germany via Multidimensional Optimization: Insights to Operationalise the Diet-Health Dimension

Abstract

\n \n \n Development of a diet optimization methodology, forming the next generation of food-based dietary guidelines (FBDG) in Germany, to identify dietary changes accounting for various dimensions: diet-health relations, environmental impact, and nutrient needs while staying culturally acceptable.\n \n \n \n Three parameters define the German Nutrition Optimization Model (GNOM): The decision variables, which are observed food intakes (FoodEx2 food grouping); acceptability constraints (acceptability upper limits (AL) are set for foods based on P95), and the linear objective function. The latter consists of three components that are weighted between each other and minimizes environmental impact (greenhouse-gas emissions and land use), diet-related health burden (disability adjusted life years), and relative deviation from the observed dietary intake (cultural acceptability). Also, deviations from nutritional needs for 39 nutrients are minimized. Five models were run on the adult population by increasing weight on diet-health and decreasing weight on cultural acceptability progressively (by steps of 20%, from 0% in model 1 (M1) to 80% in model 5 (M5)), with a fixed environmental weight at 20%. Dietary changes are exemplary described for fruits, vegetables, whole grains and red meat.\n \n \n \n All models satisfied nutrient needs and, compared to the observed diet, increased in fruits, vegetables, and whole grains and decreased in red meat; dietary changes were higher with increasing weight on diet-health. Compared to the observed intake (174,4g/d),\xa0fruits increased moderately in M1–3 (205,7g/d\xa0- 338,8g/d)\xa0and reached the AL of 552g/d\xa0in\xa0M4 and M5. Vegetables reached the AL of 267g/d\xa0in\xa0every model (observed intake: 96,3g/d)\xa0except M1 (261,5g/d).\xa0Whole grains increased progressively from 13g/d\xa0in\xa0observed intake to 16,3g/d\xa0and 16,7g/d\xa0in M1 and M2, 61,9g\xa0and 67,9g\xa0in M3 and M4 and increased strongly to 250,7g/d\xa0in M5. The observed amount of red meat was 34,4g/d,\xa0which dropped from 2,5g/d\xa0in M1 to 0g/d\xa0in\xa0M5.\n \n \n \n This methodology accounts for multidimensional requirements in FBDGs and is flexible regarding the importance given to each dimension. Preliminary results suggest that using this innovative approach to operationalize diet-health relations, GNOM is able to help derive German FBDG.\n \n \n \n German Federal Ministry of Food and Agriculture.\n