Dear Doctor: I read about a study that said smelling junk food you want to quit eating -- hello, pizza and donuts! -- will stop your craving. Is that really true? I want to eat healthier, but some foods are so hard to resist.
Dear Reader: This particular theory hadn’t crossed our radar until we read your letter, but we did a bit of digging and found the study you’re referring to. It was conducted by researchers at the University of South Florida and published at the start of the year in the Journal of Marketing Research.
The study's findings were as you say -- the sustained scent of a tempting snack food had the effect of easing the craving for that snack. That’s somewhat ironic, considering the point of the study was to examine more closely the practice of using ambient scent in public settings as a marketing ploy.
These ambient scents are part of an increasingly common practice in which retailers infuse areas with seductive smells to act as "aroma billboards," as one advertising company put it, to drive food sales. Anyone within sniffing distance of a Cinnabon stand in a mall has directly experienced this technique. Stories about the practice mention chocolate-scented strips placed on vending machines in California that caused the sales of Hershey bars to triple, a grocery store in New York whose bakery sales spiked whenever the scent of fresh-baked bread was pumped through the aisles, and the use of a variety of hidden scent machines throughout Disney properties to encourage spending. The practice is used in nonfood-related marketing, too, with a variety of pleasant scents used to make shoppers subliminally happy in order to loosen their purse strings.
According to the study you asked about, it turns out there’s an important catch when it comes to the scent-driven marketing of food: The researchers found that whether or not a scent triggered a craving was directly related to the amount of time someone spent smelling it. The tests were conducted in several sites, including a grocery store and a middle school cafeteria.
Researchers used a hidden nebulizer, which is a device that broadcasts scent. Individuals were exposed to alternating pairs of scents, one of a healthful food, and one of a junk food item. The scent of strawberries was paired with the aroma of chocolate chip cookies, and the scent of apples was paired with that of pizza. A quick whiff of a cookie -- 30 seconds or less -- often led to the cookie being selected rather than the strawberry. But when the cookie scent lingered for 2 minutes or more, the cookie lost its allure, and participants chose to eat the strawberry instead. The apple-pizza combo had the same time-dependent results. The takeaway is that by inhaling the scent of a tempting food long enough, you’ll move past craving it and arrive at the point where the scent itself has satisfied the craving.
A final word -- this was a single experiment on a complex subject, and scientists, including the researchers, agree further study is needed to fully understand the results.
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