A shorter shelf life may make packaged food appear fresher, more natural and healthier. New research, however, suggests shoppers may be relying on a misleading perception rather than meaningful differences in ingredients or nutrition.

Researchers at the University of British Columbia Sauder School of Business in Canada found that consumers often use shelf life as a mental shortcut when evaluating food. A longer shelf life can reflect packaging quality rather than heavy processing.

The research team, which included researchers from China, conducted experiments involving potato chips, pasta sauce, mayonnaise and granola bars. Participants compared products carrying different shelf life information and repeatedly favored options that would expire sooner.

Shoppers consistently rated foods with shorter shelf lives as more natural and healthier. They did so even when nutritional facts and ingredients were nearly identical or when packaging alone explained the difference in freshness.

In one experiment involving mayonnaise, the products differed only because one had a better seal that allowed it to remain fresh longer. That product was no more processed, yet participants still considered the option with the shorter shelf life more natural.

Even when researchers clearly indicated that improved packaging helped a product last longer, participants continued to use shelf life as a gauge. The pattern suggested that expiration information could outweigh an explanation about packaging technology.

Participants also judged potato chips with a shelf life of five months as more natural and healthier than nearly identical chips lasting nine months. The stated duration affected perceptions despite the close similarity between the products.

Nearly 70% of participants selected a pasta sauce with a shelf life of one year when encouraged to prioritize natural foods. Selection fell to 43% when researchers shifted the focus toward reducing food waste and protecting the environment.

Participants also associated longer shelf life with reduced waste because food would not spoil as quickly. The findings were published in the Journal of Consumer Psychology earlier this year.

“Our research shows consumers are using shelf life as a shortcut for judging whether foods are natural,” coauthor Yann Cornil, an associate professor at UBC Sauder, told Fox News Digital. “It sometimes can be diagnostic, but shelf life is also very much dependent on the quality of the packaging, which has nothing to do with food naturalness.”

Cornil called the shortcut “misleading” and noted that packaging has improved dramatically, much as refrigeration did 60 years ago. Better seals and packaging that controls moisture can preserve freshness without requiring additional preservatives.

The tendency to associate shorter shelf life with less processing could lead shoppers to pass over foods that are just as healthy while choosing products more likely to spoil. Canned beans, frozen fruits and vegetables, and dried oats can remain fresh for months or years because of packaging and preservation methods.

Kelly Springer, a New York based registered dietitian and founder and CEO of Kelly’s Choice, was not involved in the research. “A shorter shelf life does not automatically mean a food is healthier,” she told Fox News Digital. “Better seals, oxygen barriers and moisture-control packaging help foods stay fresh longer while maintaining quality and safety.”

Springer said guacamole can last longer under refrigeration because of high pressure processing and packaging technology rather than preservatives. Milk, yogurt and kefir can also remain fresh longer because of pasteurization and fermentation, not necessarily because of added ingredients.

“Don't judge a food by its shelf life,” Springer said. “Turn the package over, read the nutrition label and make decisions based on what's inside.”

Springer recommended focusing on fiber, protein, added sugar and sodium instead of relying on an expiration date alone. Cornil also identified saturated fat content as potentially problematic and said ingredient information may provide a more useful signal of processing.

“Too many ingredients, in particular ingredients [such as] additives and preservatives that you can't recognize, or can't even pronounce, may be a signal of too much processing and unhealthiness,” Cornil said. “It's not always true, but I would say that it is more diagnostic than shelf life information.”

The issue carries added relevance as consumers seek to reduce their intake of ultra processed foods. Researchers noted that roughly 55% of Americans’ daily caloric intake comes from such products, making careful label reading more informative than shelf life alone.