Meeting the EAT-Lancet ‘healthy’ diet target while protecting land and water resources

Healthy diets are known for their co-benefits of reducing environmental impacts and enabling the same agricultural resources to feed a larger human population. The EAT-Lancet (healthy reference) diet allows for compound benefits to human health and the ecosystem. It is unclear, however, to what extent the requirements of the EAT-Lancet diet may be sustainably met at the global scale. Here we combine a spatially distributed agro-hydrological model with a linear optimization analysis to relocate crops, minimizing, at the country scale, the irrigation-water consumption while improving the worldwide achievement of the EAT-Lancet nutritional goals. To that end, we define six dietary scenarios based on country-specific dietary habits from religion-related traditions, and existing livestock production systems, maintaining the same agricultural trade patterns (import–export relations). Our results suggest that an optimized global cropland allocation, and an adjustment in trade flows, would allow the global population to be fed with the EAT-Lancet diet, with a global reduction of the cultivated area of 37–40%, irrigation-water consumption of 78% (±3%), and unsustainably irrigated areas of 22%. The adoption of the EAT-Lancet diet increases the global food trade share of global food production, measured in kilocalories, from 25% (baseline) to 36% (±2%).