People Waste More Food When They Know The Scraps Will Be Composted

When it comes to food waste, education and action cancel each other out.

People Waste More Food When They Know The Scraps Will Be Composted
[Photo: wavemovies/iStock]

Conscientious people usually feel guilty about leaving food scraps on their plates, but if they know that those leftovers will be sent to compost, then they waste just as much as diners who don’t care about food waste at all. That is, says a new study from Ohio State University, the proper disposal of leftovers cancels out efforts to educate diners.


These contradictory effects have implications for food policy, whether you’re a government trying to stop food waste, or a restaurant trying to do the right thing. After all, if you are a conscientious restaurateur, you might first try to educate your customers, and then to dispose of any waste in as environmentally responsible a way as possible. And of course, you’d use the composting angle as positive marketing for your business.

The study, led by OSU graduate student Danyi Qi, examined the eating behavior of 266 students. Participants were monitored throughout a meal to see how they behaved. The food was self-serve, and participants were allowed to take as much as they wanted from a selection of sandwiches, chips, and apple slices. Sharing and doggy bags were prohibited, and the trays were weighed after the meal to determine the amount of waste.

[Photo: sanddebeautheil/iStock]

Prior to eating, participants were given cards with information about either the problems of food waste or financial literacy (this was the control group). Then, half the participants were told that their leftovers would be composted, the other half that any waste would be sent to landfill.

The results showed that the education had a huge effect. Those who read the food-waste leaflets left 77% less food than those who remained ignorant. They were also 39% more likely to clean their plates.

But this gap didn’t exist out if the educated participants were also given the information that the waste would be composted. “It seems that if they feel that the social and environmental cost is lower, they may feel less guilty and that may cause them to waste more,” Qi told the OSU Newsroom.

What can be done about this annoying behavioral glitch? To answer that, we have to think of the goals. The most important thing is to reduce food waste. Disposing of waste ethically is fine, but it’s better not to waste food to begin with. With that goal, it’s clear that education is more important. And if you’re a restaurateur, you might still consider sending waste for composting–just keep quiet about it.

About the author

Previously found writing at, Cult of Mac and Straight No filter.