The DELTA Model: Understanding the Ability of the Global Food System to Deliver Nutrition

Abstract

ObjectivesWhile the environmental, social and economic sustainability of the current global food system attracts increasing research, its ability to nourish the global population must be prioritised. Our objective was to produce a computational model illustrating the nutritional adequacy of the current global food system and allow investigation of proposed global food system scenarios. MethodsData from several public databases was collected to describe food production, processing and waste in the global food system. Data was also sourced for global demographics and human nutritional requirements for 29 nutrients. These data were used to construct the DELTA Model. The model takes global food production scenarios as its input and calculates the nutrients available for human consumption, after consideration of animal feed uses, waste and non-food use. This amount of available nutrients was then compared to demographically weighted target daily intakes, allowing the nutritional adequacy of the food system to be quantified. The DELTA Model also includes nutrient bioavailability adjustments for protein and essential amino acids to ensure accurate conclusions are drawn for these nutrients, demonstrated to be pressure points in global nutrition previously. The model is freely available online. ResultsModelling the 2018 global food system showed that neither energy nor protein are limiting under conditions of equal food distribution, even with a population increase of 1 billion. Halving food waste between farm and consumer allows for sufficient energy and protein availability to nourish the forecast 2050 population of 9.7 billion using current production volumes. However, numerous micronutrient insufficiencies emerge in these future scenarios. Considering the bioavailability of protein and amino acids reduced the availability of these nutrients by between 2% and 17% compared to simply considering the content of foods, emphasizing the importance of this consideration. ConclusionsIt is essential that nutritional adequacy is at the forefront of the sustainable food system debate. The DELTA Model allows both experts and non-experts to better understand food system dynamics in global nutrition, aiding the discussion of what changes to the food system may be appropriate. Funding SourcesFunding from the Riddet Institute Centre of Research Excellence.