The world’s food system is in disarray. One in ten people is undernourished. One in four is overweight. More than one-third of the world’s population cannot afford a healthy diet. Food supplies are disrupted by heatwaves, floods, droughts and wars. The number of people going hungry in 2020 was 15% higher than in 2019, owing to the COVID-19 pandemic and armed conflicts1.
Our planetary habitat suffers, too. The food sector emits about 30% of the world’s greenhouse gases. Expanding cropland, pastures and tree plantations drive two-thirds of the loss in forests (5.5 million hectares per year), mostly in the tropics2. Poor farming practices degrade soils, pollute and deplete water supplies and lower biodiversity.
As these interlinkages become clear, approaches to food are shifting — away from production, consumption and value chains towards safety, networks and complexity. Recent crises around global warming and COVID-19 have compounded concerns. Policymakers have taken note.
In September, the United Nations secretary-general, António Guterres, will convene a Food Systems Summit. This is only the sixth UN summit on food since 1943, and the first with heads of states in the UN General Assembly. A group of leading scientists, known as the Scientific Group, has been tasked with ensuring that the science underpinning the 2021 summit is robust, broad and independent. We, the authors, are this group’s chair and vice-chairs. Although such approaches are familiar in areas such as climate change and biodiversity, this marks the first time that scientists have been explicitly