New Study Reveals Age-Related Patterns in Food Waste and Emissions

Household food waste significantly contributes to both global food loss and greenhouse gas emissions, impacting not only food security but also the environment. Despite its importance, much remains unknown about the types of food wasted most frequently and the specific demographic groups responsible for it. Recent research by Japanese scientists provides new insights into the relationship between household food waste, food type, and demographic factors, shedding light on strategies to address this pressing issue in aging developed nations like Japan.

Food production is fundamental to human societies, yet it imposes a considerable environmental burden, consuming vast amounts of energy and resources. Shockingly, about a third of all food produced globally is never consumed, emphasizing the need to minimize waste as a step toward sustainability. In Japan alone, 2021 government estimates show that households generated an astounding 2.47 megatons of food waste, a substantial portion of which was edible, highlighting the scope for improvement in waste reduction.

To address this challenge, a research team led by Associate Professor Yosuke Shigetomi from Ritsumeikan University, Japan, in collaboration with scientists from Nagasaki, Kyushu, and Tokyo universities, investigated food waste patterns within Japanese households. Their study, published in Nature Communications on October 21, 2024, provides valuable insights into the types of food that contribute most to household waste, the demographics associated with higher waste levels, and the emissions tied to wasted food.

The researchers analyzed data from existing surveys, focusing on both edible and inedible portions of over 2,000 food products across various categories. They also examined socioeconomic and demographic data to understand how age and other factors influenced food waste patterns. One key finding was that food waste per person increases considerably with the age of the household head, with older households generating nearly twice the food waste compared to younger ones. Vegetables emerged as the most frequently wasted food type, followed by ready meals, fish, and seafood, which also have substantial greenhouse gas implications.

Dr. Shigetomi emphasized the contribution of Asuka Ishigami, a former student from Nagasaki University, in collecting and analyzing fundamental data for the study. This collaborative effort allowed the team to detail how specific food categories impact waste and emissions differently. The researchers discovered that vegetables, while frequently wasted, also contribute notably to emissions when discarded. Ready meals and seafood, while less common in terms of volume, add considerably to greenhouse gas emissions.

The study’s results suggest that strategies for reducing household food waste should be tailored to specific age groups. Educational campaigns could help older generations understand how to better manage and minimize food waste, while broader awareness efforts could encourage all age groups to adopt sustainable consumption habits.

The findings underline the need for targeted policy interventions. For instance, focusing on reducing vegetable and meat waste can have dual benefits, as both contribute significantly to greenhouse gas emissions. Dietary trends, particularly the shift toward vegetarianism as a climate-conscious choice, may also need to be adapted to different age groups to foster lasting change, said Dr. Shigetomi added.

This study’s insights are expected to guide policies aimed at reducing food waste, especially in developed countries with aging populations. Through educational programs, improved food management practices, and targeted dietary recommendations, Japanese households—and potentially those in similar nations—can play a vital role in minimizing food waste and mitigating its environmental impact.

(Source: Ritsumeikan University)