UBC study links shorter shelf life to perceptions of naturalness and health

Nutrition experts have long cautioned against the consumption of ultra-processed foods, citing risks such as obesity, cardiovascular disease, and diabetes. In response, many consumers are advised to prioritize more natural food options. However, a new study from the University of British Columbia (UBC) Sauder School of Business suggests that shoppers often rely on a simple heuristic to determine the naturalness of a product: its shelf life. The research indicates that consumers frequently use the duration a product remains fresh as a shorthand for its healthiness, even when this metric is not a reliable indicator of nutritional quality or processing level.

The study, titled “Naturalness against environment-friendliness: The impact of shelf life on food perceptions and purchase decisions,” was published in the Journal of Consumer Psychology. The research team, led by UBC Sauder Associate Professor Dr. Yann Cornil, along with Dr. Dan Liu of Jinan University and Dr. Xiaobing Xu of Hainan University, conducted a series of experiments to explore how shelf life influences consumer perceptions and purchasing behavior. Their findings reveal a complex interplay between the desire for natural foods and the environmental implications of food waste.

In one experimental condition, participants were asked to compare two types of potato chips: one with a five-month shelf life and another with a nine-month shelf life. The results showed that participants consistently rated the chips with the shorter shelf life as more natural and healthier. Conversely, the chips with the longer shelf life were perceived as more environmentally friendly and better for reducing waste. This initial finding established a clear dichotomy in consumer perception, where naturalness and environmental responsibility were viewed as competing priorities.

Further experiments explored how contextual framing affects these decisions. In a study involving pasta sauces with one-year and three-year shelf lives, researchers manipulated the emphasis placed on different values. When participants were reminded of the importance of consuming natural foods, nearly 70 percent chose the sauce with the one-year shelf life. However, when the researchers emphasized the importance of protecting the environment, the preference for the shorter-shelf-life product dropped significantly to 43 percent. This shift demonstrates that consumer choices are highly sensitive to the specific cues provided by marketing or personal values.

The researchers also tested whether providing explicit information could override the shelf-life heuristic. In one scenario, participants were shown mayonnaise jars where the only difference between the shorter and longer shelf-life versions was the packaging; specifically, the longer-lasting version featured a high-performance seal. Despite being informed that the extended shelf life was due to superior packaging rather than additional processing, participants still opted for the mayonnaise with the shorter life when naturalness was the primary concern. This suggests that the mental shortcut associated with shelf life is robust and resistant to logical counter-evidence.

Similar results were observed in tests involving granola bars. Participants were presented with two bars that had nearly identical ingredients and nutritional information but different shelf lives. When the context emphasized naturalness, consumers again preferred the product with the shorter shelf life. These findings highlight that the association between shelf life and naturalness persists even when objective data suggests that the products are equivalent in terms of health and composition. The study underscores the power of peripheral cues, such as shelf life, packaging, and marketing, in shaping consumer judgments.

Dr. Cornil explains that consumers are often overwhelmed by the amount of information available on food labels, including ingredient lists and nutritional facts. In this complex environment, shoppers tend to rely on peripheral cues to make quick decisions. “We provide all the necessary information to make a rational choice… But it’s a lot to process,” Dr. Cornil notes. Instead of analyzing every detail, consumers use shelf life as a mental shortcut to infer whether a product is natural. This heuristic, while intuitive, can lead to suboptimal choices that do not align with actual nutritional value or environmental impact.

The study is particularly timely given the high prevalence of ultra-processed foods in modern diets. Approximately 46 percent of Canadians’ daily caloric intake comes from ultra-processed foods, a figure that rises to about 55 percent in the United States. These foods are often derived from substances extracted from sugars, oils, and starches, and are significantly altered from their natural state. They can be high in sodium, saturated fat, and added sugar, while being lower in essential nutrients. As nutrition science shifts its focus from simply limiting fat and sugar to reducing overall processing, the perception of naturalness has become a critical factor in consumer behavior.

While there is some truth to the association between shelf life and processing, Dr. Cornil points out that it is not absolute. Improvements in packaging technology have dramatically extended the shelf life of many foods without increasing their processing level. “To some extent they are correct, because the more you extend the shelf life of a food, the more likely it went through this ultra-processing technique… but not necessarily,” he says. Better packaging, similar to the introduction of refrigeration decades ago, has improved food conservation. However, consumers often overestimate the link between shelf life and naturalness, leading to the unnecessary discarding of food that is still safe and healthy to eat.

The study is the first of its kind to demonstrate the tension between environmental friendliness and naturalness, as well as the strength of the shelf-life heuristic. Dr. Cornil emphasizes that the effect persists even when consumers are provided with nutritional information and explanations about packaging. “The fact that we still find this effect even when we provide nutrition information, and even when we make consumers understand that packaging is responsible for the longer shelf life and not processing, is really interesting,” he says. This misleading heuristic can lead consumers to choose foods that are more likely to be wasted, thereby undermining both health and environmental goals. The findings suggest that future efforts to reduce food waste and improve dietary quality may need to address these deep-seated perceptual biases.

Subject of Research: Consumer Psychology and Food Science

Article Title: Foods with shorter shelf life are seen as more natural and healthier: UBC study

Article References: Foods with shorter shelf life are seen as more natural and healthier: UBC study. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: food waste, consumer behavior, shelf life, naturalness, UBC, ultra-processed foods, Journal of Consumer Psychology, Foods, shorter, shelf, life, seen