Growing for good: producing a healthy, low greenhouse gas and water quality footprint diet in Aotearoa, New Zealand.

Food production plays a central role in the health of humanity and our environment. New Zealand produces a large amount of food, but it is unknown if it can produce enough of the right crops in the places to better the health of New Zealanders, profitably, while maintaining New Zealand's primary production exports and meeting ambitions to lower greenhouse gas (GHGs) emissions and nutrient losses to water. We tested two scenarios that aimed at delivering a healthy diet while maximising profit and minimising GHGs (climate-focused scenario) or losses of nitrogen (N) and phosphorus (P) to water (freshwater-focused scenario). Land use change was targeted to areas not currently meeting bottom lines for N or P loss but needed to spill over to other areas to meet dietary targets in both scenarios. The maximum cost of the required land use change was about 1% of the primary sector's export revenues, and orders of magnitude less than the estimated savings for the health system from an optimised diet. We conclude that shifting productive land uses can help meet environmental targets for GHGs, N and P while saving money and improving the health of its people.