Half of food system greenhouse gases come from food waste

A recent study published in Nature Climate Change found that about half of greenhouse gas emissions from the global food system come from food loss and waste. Researchers tracked the entire cradle-to-grave process of food, from production to disposal, and found that a significant portion of these emissions were caused by human behavior patterns rather than technological issues.

Why it matters: ‘Behavioral problems’ identified as key cause

The reason this study is attracting attention is that it defines the root cause of the food waste problem as ‘misbehaviour.’ Misbehavior here includes overbuying, overeating, impulsive food consumption, and improper food management at home.

The United Nations Environment Program (UNEP)'s 2024 Food Waste Index report also shows that billions of tons of food are wasted annually worldwide, and reducing this by half is set as a key task of Sustainable Development Goal (SDG) 12.3. However, it has been pointed out that while most policies to date have focused on supply chain efficiency, approaches to changing consumer behavior have been relatively lacking.

Where did this problem begin: The paradox of food surplus after the Green Revolution

Historically, food issues have been dealt with from the perspective of ‘scarcity’. The Green Revolution of the 1960s dramatically increased agricultural productivity and laid the foundation for feeding 9 billion people. However, in this process, a food surplus occurred, especially in developed countries, which led to a new environmental problem of food waste.

A 2016 study published in Environmental Science & Technology was the first to quantify the climate burden of food surplus, and since then systematic research on household food waste behavior has begun to accumulate. In 2021, the 'Household Waste Behavior Framework', which categorizes consumer food waste behavior, was presented, increasing academic interest in the impact of individual behavior on the environment.

Meanwhile, food security remains a serious problem in developing countries such as sub-Saharan Africa. This shows a paradoxical situation where there is an imbalance in food distribution around the world, with surplus occurring in some regions and deficiency occurring simultaneously in other regions.

Future outlook [AI analysis]

The results of this study are likely to provide important implications for climate change response policies. First, it is expected that food waste reduction policies will expand beyond supply chain efficiency to induce changes in consumer behavior. Improvements in food labeling, education on appropriate intake levels, and nudge policies to curb impulse purchases can be reviewed.

Second, a customized approach that takes into account differences in food waste patterns depending on income level appears to be necessary. Curbing excessive consumption is likely to be prioritized in high-income countries, while improving storage and distribution infrastructure is likely to be prioritized in low-income countries.

Third, in order to achieve the Sustainable Development Goal (SDG 12.3) of reducing food waste by half by 2030, monitoring and intervention strategies for individual eating habits and purchasing behavior are expected to be strengthened. However, regulations on individual behavior may lead to controversies over invasion of privacy, so a cautious approach is required during the policy design process.