Scientific Targets for Healthy Diets* Food group Food subgroup Reference diet (g/day) Possible ranges (g/day) Whole Grains All grains 232 0 to 60% of energy Tubers/Starchy Vegetables Potatoes, cassava 50 0 to 100 Vegetables All vegetables 300 200 to 600 Fruits All Fruits 200 100 to 300 Dairy Foods Dairy Foods 250 0 to 500 Beef, lamb, pork 14 0 to 28 Protein Sources Chicken, other poultry 29 0 to 58 Eggs 13 0 to 25 Fish 28 0 to 100 Dry beans, lentils, peas 50 0 to 100 Soy 25 0 to 50 Nuts 50 0 to 75 Added fats Unsaturated oils 40 20-80 Added sugars All sweeteners 31 0 to 31 * See Table 1 for a complete list of scientific targets for a 2500 kcal/day healthy reference diet The Commission has integrated, with the quantification of universal healthy diets, global scientific targets for sustainable food systems. The objective is to provide scientific boundaries to reduce environmental degradation arising from food production at all scales. The quantification of scientific targets for the safe operating space of food systems in the world, was done for the key environmental systems and processes where food production plays a dominant role in determining the state of the planet. There is strong scientific evidence that food production is among the largest drivers of global environmental change due to its contributions to greenhouse gas (GHG) emissions, biodiversity loss, freshwater use, eutrophication, and land-system change (as well as chemical pollution, which is not assessed by this Commission). In turn, food production depends upon the continued functioning of these biophysical systems and processes in regulating and maintaining a stable Earth system. These systems and processes thereby provide a necessary set of globally systemic indicators of what constitutes sustainable food production. The Commission concludes that these quantitative scientific targets for sustainable food systems, constitute universal and scalable planetary boundaries for the food system, (Table 2). However, the uncertainty range for these food boundaries remain high, due to the inherent complexity in Earth system dynamics from local ecosystems to the functioning of the biosphere and the climate system. Scientific Targets for Sustainable Food Production Earth system process Control variable Boundary Uncertainty Range Climate change GHG (CH4 and N2O) emissions 5 Gt CO2-eq yr-1 (4.7-5.4 Gt CO2-eq yr-1) Nitrogen cycling N application 90 Tg N yr-1 (65-90 Tg N yr-1) (90-130 Tg N yr-1) Phosphorus cycling P application 8 Tg P yr-1 (6-12 Tg P yr-1) (8-16 Tg P yr-1) Freshwater use Consumptive water use 2,500 km 3 yr-1 (1000-4000 km 3 yr-1) Biodiversity loss Extinction rate 10 E/MSY (1-80 E/MSY) Land-system change Cropland use 13 M km 2 (11-15 M km 2)

Clearer understanding is needed of the premises underlying SI and how it relates to food-system priorities.

Both the global average per capita consumption of meat and the total amount of meat consumed are rising, driven by increasing average individual incomes and by population growth. The consumption of different types of meat and meat products has substantial effects on people’s health, and livestock production can have major negative effects on the environment. Here, we explore the evidence base for these assertions and the options policy-makers have should they wish to intervene to affect population meat consumption. We highlight where more research is required and the great importance of integrating insights from the natural and social sciences.

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