By John Salak –
The nose knows what the body likes—and that’s where eating problems probably start. Food decisions people make are usually triggered by their all-knowing nose to such an extent that many baked goods brands intentionally pump up the aromas of their products to entice would-be passerbys to stop and grab something to eat.
Here’s the newest rub to this olfactory equation. Smell may dictate what people eat next but what someone has just chowed down on apparently affects their sense of smell, which in turn impacts an individual’s next food choice.
Northwestern University, in fact, recently discovered that people became less attuned to these aromas thanks to whatever they’re just eaten. Does this mean would be dieters can turn off their food triggering mechanism and save some calories? Perhaps.
Northwestern’s scientists, for example, note that it’s possible to munch on a few cookies at home or the office and then be less inclined to get drawn into a bakery by the smell of a pain au chocolat. Of course, fending off that emotional trigger did require eating cookies to begin with.
The university’s study found that participants eating cinnamon buns or pizza, for example, were less likely to perceive “meal-matched” odors or similar smelling foods. Effectively, the findings showed that smell affects what people eat and what people eat affect their sense of smell.
Ultimately, this give and take from the nose may be the result of an evolutionary benefit that helped earlier humans achieve a more balanced diet, according to the study’s author, Thorsten Kahnt, an assistant professor at Northwestern University Feinberg School of Medicine.
“If you think about our ancestors roaming the forest trying to find food, they find and eat berries and then aren’t as sensitive to the smell of berries anymore,” Kahnt said. “But maybe they’re still sensitive to the smell of mushrooms, so it could theoretically help facilitate diversity in food and nutrient intake.”
Kahnt admits this tradeoff doesn’t have a current hunter-gatherer adaptation, but it may still be important to an individual’s wellbeing. Olfactory issues could lead to disordered eating patterns and obesity, he warned. It is possible such problems could disrupt sleep as well.
The university’s team used brain imaging, behavioral testing and non-invasive brain stimulation to get a sense of how smell impacts learning and appetite, particularly as it pertains to psychiatric conditions like obesity, addiction and dementia.
“After the meal, the olfactory cortex didn’t represent meal-matched food odors as much as food anymore, so the adaptation seems to be happening relatively early on in processing,” Kahnt said. “We’re following up on how that information is changed and how the altered information is used by the rest of the brain to make decisions about food intake.”