Population and food systems: what does the future hold?

The ability of food systems to feed the world’s population will continue to be constrained in the face of global warming and other global challenges. Often missing from the literature on future food security are different scenarios of population growth. Also, most climate models use given population projections and consider neither major increases in mortality nor rapid declines in fertility. In this paper, we present the current global food system challenge and consider both relatively high and relatively low fertility trajectories and their impacts for food policy and systems. Two futures are proposed. The first is a “stormy future” which is an extension of the “business as usual” scenario. The population would be hit hard by conflict, global warming, and/or other calamities and shocks (e.g., potentially another pandemic). These factors would strain food production and wreak havoc on both human and planetary health. Potential increases in mortality (from war, famine, and/or infectious diseases) cannot be easily modeled because the time, location, and magnitude of such events are unknowable, but a challenged future is foreseen for food security. The second trajectory considered is the “brighter future,” in which there would be increased access to education for girls and to reproductive health services and rapid adoption of the small family norm. World average fertility would decline to 1.6 births per woman by 2040, resulting in a population of 8.4 billion in 2075. This would put less pressure on increasing food production and allow greater scope for preservation of natural ecosystems. These two trajectories demonstrate why alternative population growth scenarios need to be investigated when considering future food system transitions. Demographers need to be involved in teams working on projections of climate and food security.