What is DELTA?

The DELTA Model is a global food system mass balance that uses information about current food production to predict the nutrition available to the average global citizen both now and in the future.

The model lets the user adjust the production of different food groups, the degree of food waste, and the global population to see the impact of these changes on human nutrition.

Future versions of the model will include estimates of the impacts of food system scenarios on land use, greenhouse gas production, and other resource constraints.

Why use DELTA?

A challenge we face is our ability to sustainably nourish an increasing global population without exceeding the capacity of the planet. There are many different ways of approaching this challenge, and many suggestions for what the answer may be.

The DELTA Model has been developed to help people explore this challenge themselves by manipulating the major components of the food system to see the impact on the supply of key nutrients.

How to use DELTA

The model is found by selecting ‘Explore the Future’ from the menu. The side-panel on the left contains the user adjustable settings.

  • Scenario Options contains high level scenario settings and enables the user to switch between predefined food system options
  • Primary Production contains the annual production of each of the food product groups in millions of tonnes
  • Secondary Modifiers contains a range of other model options for the user to select

Core Engine

Food production information is taken from the UN Food and Agriculture Organisation (FAO) Food Balance Sheets and combined with food composition data from the United States Department of Agriculture (USDA) FoodData Central. The core of DELTA is a model that allows the user to modify food production from the FAO food balance sheets and view the impact on the nutrition available to the average global citizen.

This image describes the Delta Model and it's components as a workflow
The Delta Model generates viable outcomes from complex initial scenarios.


  • Design: Andrew Fletcher1,2, Jeremy Hill1,2, Simon Hunter4, Warren McNabb1
  • Programming: Andrew Fletcher1,2, Nick Smith1, Joshua Ghezzi3, Christopher Pearce3
  • Research and Nutrition: Lakshmi Acharya1, Shalome Bassett1,2, Natalie Russell3, Caroline Gunn2, Nick Smith1, Warren McNabb1
  • Resources: We would like to thank shiftn for permission to reproduce the global food system map.


  • Olivia Finer2, Andrew Fletcher1,2, Jeremy Hill1,2, Warren McNabb1, Nick Smith1, Charlotte Van Der Lee2

Thoughts for Food

  • Olivia Finer2, Andrew Fletcher1,2, Cody Garton4, Jeremy Hill1,2, Wayne Martindale5, Warren McNabb1, Nick Smith1, Charlotte Van Der Lee2
  1. Riddet Institute
  2. Fonterra Cooperative Group Limited
  3. KPMG
  4. Independent
  5. University of Lincoln

DELTA Model Data Sources

  • Food Production: United Nations Food and Agriculture Organisation (FAO) Food Balance Sheets
  • Food Composition: United States Department of Agriculture (USDA) FoodData Central
  • Demographics: UN FAO Annual Population and United Nations Department of Economic and Social Affairs (DESA) World Population Prospects
  • Nutrition Requirements: European Food Safety Authority (EFSA) (2017) Dietary reference values for nutrients and UN FAO (2013) Dietary protein quality evaluation in human nutrition.
  • In-home LossesUN FAO (2011) – Global Food Losses and Food Waste
  • Animal Feed Allocation: Mottet et. al. (2017) Livestock: On our plates or eating at our table? A new analysis of the feed/food debate