The scenario is typical: You go to the fridge and pull out leftovers from Tuesday’s dinner. Maybe you had pasta or chicken or a burrito. Could be whatever you couldn’t finish from a particularly big salad. Whatever the case, it prompts a recurrent question we all face in situations like these, one that has likely been part of our genetic makeup since the dawn of time. Is the food safe to eat?
According to some new research from McIntire Professor Christine Kim, it seems that many of us are more tempted to more quickly chuck foods in the trash that we think are healthier.
Kim’s paper, “To Dispose or Eat? The Impact of Perceived Healthiness on Consumption Decisions for About-to-Expire Foods,” forthcoming in the Journal of Marketing, sheds light on an issue that connects food waste, consumer behavior, and public policy in new and meaningful ways. Co-authored with Young Eun Huh of the Korea Advanced Institute of Science and Technology (KAIST) and Brent McFerran of Simon Fraser University, their paper may have important implications for how we approach food labeling, consumption, and reducing food waste across the world.
The core of Kim’s research investigates the surprising behavior that consumers tend to discard food based on perceptions of its innate healthiness. Specifically, the study reveals that people are more likely to throw away food they perceive as better for them when it is nearing its expiration date. This phenomenon stems from a widespread yet misguided assumption—a commonsense belief referred to as a “lay theory”—that healthy food expires faster than its less nutritious counterparts do.
“What the paper talks about is this lay theory that healthy food, like fresh produce, does indeed go bad quickly,” says Kim. But the problem that leads to more food waste by consumers arises when overgeneralization of this belief gets applied it to all kinds of foods, even those that do not differ significantly in expiration dates based on healthiness.
Inspiration Behind the Research
The impetus for Kim’s research came from a personal experience during her time teaching at the Hong Kong University of Science and Technology (HKUST), where she encountered challenges in grocery shopping due to her remote location.
“I was living up on a mountain, and I didn’t have a car. So, grocery shopping became a chore where I would think about how long the food would last,” Kim recalls. As she began prioritizing food longevity over other factors, she noticed an emerging pattern: “I started avoiding healthier foods because I thought they wouldn’t last as long.” This realization, combined with her academic curiosity about lay theories, led Kim to question whether others shared the same intuition.
After discussing the concept with her then-neighbor, colleague, and now co-author Huh, they deduced that many people intuitively believe healthy food spoils more quickly and decided to investigate further. As Kim explains, “Even though two products, like healthy and less healthy potato chips, are processed the same way and have the same ingredients, people still think the healthier version will expire faster.”
Policy, Sustainability, and World Hunger Implications
Implications for Kim’s research extend beyond individual consumer behavior to invite broader discussions about waste reduction, government policy, and food insecurity. One key aspect of the paper concerns the perception of food expiration and its ability to lead to more waste, particularly of healthier items, which are often the most nutrient-dense.
“One-third of all food produced for human consumption is wasted globally—and much of that food is edible,” says Kim. Her research points to the role of package-printed expiration dates in this waste, noting that consumers often misinterpret these labels as a hard and fast safety warning, leading to unnecessary disposal.
From a policy perspective, the implications are significant. Governments can help reduce food waste by requiring more precise expiration labeling. This could also aid in the fight against hunger. “We know that people who are food insecure tend to rely more on sensory checks, like smelling or tasting food, before throwing it away. But people don’t even want to engage in checking the food; they just throw it out,” Kim explains. She admits that complexities in policy will likely make it difficult to get governments around the world to intervene in order to make expiration dates more consumer-friendly, but remains heartened to see in her research that the effect of people avoiding healthy about to expire food is lessened when an expiration date is very clearly given.
Changing Consumer Behavior
As a central focus of Kim’s research is how to influence consumer behavior, her study shows that people need different types of promotions to feel comfortable purchasing healthy food nearing expiration.
“We found that people required greater discounts for healthy foods when they were about to expire,” she says. Additionally, consumers preferred price promotions over bulk promotions for healthier items, reflecting their hesitation to stock up on foods they believed might spoil quickly. “People would rather take a smaller price discount than a bulk promotion because they are worried about having more of something they think will expire too soon,” Kim adds.
These insights offer valuable lessons for retailers and policymakers. Grocery stores, for example, could design targeted sales strategies that account for consumer concerns about the longevity of healthy foods. This could include deeper discounts for healthy items nearing expiration or clearer expiration labels, helping to reduce both food waste and financial losses for retailers.
More Work to Be Done
Kim has more research ahead about food waste. She is currently exploring new avenues for reducing waste through consumer education and engagement. One of her projects involves encouraging consumers to become more involved in food preparation, which has been shown to reduce what might otherwise be discarded. “When people are more involved in making their own meals, they are less likely to waste it,” she says.
This research underscores the importance of understanding the psychological factors that contribute to food waste and how we can mitigate them through education, policy, and smarter marketing. Kim’s work not only illuminates a critical problem but also offers solutions that could eventually have a lasting impact on how food is marketed and labeled, as well as take a step toward reducing global food insecurity and waste.
