By Kurt Knebusch | The Ohio State University
COLUMBUS, Ohio—Individualized coaching coupled with an app for tracking could help families greatly reduce some types of food waste, in turn helping combat climate change.
That’s a finding from a recent study co-led by Brian Roe, holder of the Fred N. VanBuren Professorship in Farm Management at The Ohio State University College of Food, Agricultural, and Environmental Sciences (CFAES).
“Food waste is one of the greatest sources of greenhouse gas emissions, and it’s something that nearly everyone can address in their daily lives,” said Roe, who is a faculty member in the CFAES Department of Agricultural, Environmental, and Development Economics. He is also the director of the Ohio State Food Waste Collaborative.
The study, Roe said, “is the first to tailor a food-waste intervention to every household’s individual circumstances.”
Reduce food waste, fight climate change
Reducing food waste is important in fighting climate change because most food tossed in the trash goes to landfills—an estimated 52 million tons a year in the United States alone—where it rots and produces methane, a powerful greenhouse gas.
App-assisted interventions, meanwhile, are seeing growing use for health and wellness, such as for losing weight, eating better, tracking blood sugar, and managing mental health.
For their study, which was published in the journal Resources, Conservation & Recycling, Roe and team set out to see if tailored intervention—in this case, customized one-on-one coaching aided by data collected by an app called FoodImage—can lead to greater changes in people’s behavior when it comes to reducing food waste.
“The urgency of climate change necessitates that future interventions are designed to maximize potential impacts,” the researchers wrote in the study’s introduction.
Which food waste was cut the most
Among their findings, the researchers found the largest effect of their intervention to be on plate waste, which fell by 79%, with the biggest part of that being at dinner. Plate waste is food left on the plate after someone finishes eating, such as the crust of a piece of pizza or a second helping that couldn’t be finished.
The study also reported reductions in food waste sent to a landfill, which dropped by 25%; the amount of food selected, down 19%; and the amount of food consumed, down 15%. But it saw no significant increases or decreases in food saved for later, storage cleanout waste, and food-preparation waste.
At the same time, the study also recorded no “unwanted behavioral responses” as a result of the intervention. Roe noted, for instance, that there was no overeating, and no decline in buying fresh fruits and vegetables so as to not risk wasting them. But the study did see big increases in desirable behaviors in addition to reducing food waste, such as eating less and composting.
‘Big effect’ from smaller amounts
Roe said he was a little surprised by the 79% reduction in plate waste because “most improvements in the literature are usually around 30% for an overall effect.” The 79% decline shows that “serving smaller amounts can have a big effect,” he said.
Indeed, the 79% reduction by itself would prevent more than 50 pounds of plate waste per household if sustained for a year. That’s based on the participants who received the intervention reducing their plate waste by about 1 pound per week.
Reducing plate waste is “something that can be addressed at every meal, so there were lots of opportunities for learning in response to the coaching, whereas things like storage cleanout waste occur only occasionally,” Roe said.
What the study’s participants did
The study participants who received the intervention got individually tailored coaching on ways they could reduce their household’s food waste. The coaching included an introductory lifestyle interview about factors such as the participant’s food shopping, meal preparation, and eating. The coaching also included a discussion of what the participant was willing and able to do, or not do, such as composting if living in a small apartment, and the setting of tactics, goals, and a plan.
The participants then went about their normal lives for a week while recording their food buying, use, and waste on the FoodImage app, which was invented by Roe and two of the study’s other researchers. As the week progressed, the participants received regular food waste tips by email, phone, or text. They also received further, adjusted coaching based on what the app had learned: Which tactics were working for the participant, and which ones weren’t?
Eat the peel, compost the core
Roe gave a hypothetical example of a participant in the study, a college student, who, because of the coaching they received:
- stopped throwing away the peel of the apples they eat, a part high in fiber, and started eating the peel instead
- started saving their apple cores in a bag in their freezer rather than tossing them in the trash—they couldn’t compost in their apartment—then later took them to their friend’s home in the country for composting
- switched to pouring themself less milk and cereal to start with—reducing the chance of not eating all of it—and poured more only if they found they were still hungry after that
- started buying the smallest jug of milk they could and storing it in the coldest part of the refrigerator to make it last as long as possible.
The intervention wasn’t one-size-fits-all, Roe and colleagues wrote in their study. “Rather, it was a delicate balance with the coach using motivational interviewing and Socratic questioning techniques to encourage the participant to personally identify behaviors they would like to change that reduce food waste the most.”
‘An intriguing glimpse’
The study did have “plenty of limitations,” Roe said, noting it was small, short in duration, and costly to implement. “But it provides an intriguing glimpse into what an individual customization approach could deliver,” he said.
Scaling up the study’s intervention approach, both to reduce its cost and boost its use and impact, “is where artificial intelligence would likely be needed,” Roe said. “One can imagine Noom for food waste or other sustainability practices.”
The study’s other researchers were co-leaders John W. Apolzan and Corby K. Martin, along with Danyi Qi, Robbie A. Beyl, and Karissa E. Neubig, all of Louisiana State University.
The team’s journal article, “A Randomized Controlled Trial to Address Consumer Food Waste with a Technology-aided Sustainability Intervention,” can be read online at go.osu.edu/CHze.
