Is 'Smellvertising' Sabotaging Your Diet?

Bacon frying. Buttery popcorn. Warm brownies fresh from the oven. Many a healthy eating pledge has flown out the window at first whiff of one of these mouthwatering aromas. Of course, we saw--or rather, smelled--it coming.

But what about other, sneakier ways our sniffers might be leading us to indulge?

Thanks to "smellvertising" and other nosey ploys--from artificial aromas that make us think a food is nutritious, to scents that trigger subconscious cravings (the toughest kind to resist, experts say)--companies are increasingly recruiting our nostrils to get us unwittingly hooked on not-so-healthy foods.

Here's how.

Smells permeate our primitive brain.

Smells have a funny way of wafting under the conscious radar. Unlike our other senses, the olfactory system is closely linked to the brain's centers for emotion and memory, and smells head straight there instead of being processed via the thalamus (that conscious radar), according to the Monell Chemical Senses Center, a Philadelphia-based non-profit that researches taste and smell.

Thus, with scents, we process first, and think second. And by the time we think, smells have already saturated our emotional brain--the strongest influencer of what we decide to buy, or eat, says Martin Lindstrom, who authored Buyology.

With the nose apparently having a mind of its own, you can imagine how smells can wreak havoc when we're trying to be choosy about what we eat. But seductive scents, in themselves, aren't necessarily bad for us: garlic, cinnamon, butter, coffee, bread, chocolate, peanut butter, and vanilla are rated among the most tempting. It's when these scents waft from every bakery and burger joint that we can get into trouble. And our favorite smells are increasingly canned--added artificially to food, packaging, and even the air.

Cinnabon has famously been accused of pumping a gooey cinnamon aroma into the environment around its stores to lure customers.

"Just this once?" Not likely.

As if having our emotions infused isn't enough, there's the issue of smells permeating our memory too. Driving past a Jimmy John's Gourmet Sandwich shop the other day, I noticed a neon sign in the window that read "Free Smells." Sure enough, its whiffs worked on me ... even with my car windows rolled up. I immediately conjured the smell of a smoked ham club sandwich and my mouth started to water.

Forget the free sample; companies have discovered that we don't need a taste to whet our appetites. Once a smell is lodged in our brains, not only are we more likely to gravitate to it again, scent memory research shows, but we can reproduce the smell on our own, virtually doing the advertising for them. Food companies call this "scent branding."

If that smell is combined with an image, we're even more likely to remember it, Lindstrom says in Buyology. This is why we'll get a mental picture of brownies, even the Betty Crocker logo, when we catch that signature chocolatey aroma.

Well, it smells like fruit?

When it comes to detecting flavor, the nose doesn't always know. We tend to associate foods that emit fragrance with being fresh, flavorful, or natural, but scent additives can trick the brain. "Flavoring" is casually infused into many foods to create odors: take the chicken scent of McNuggets, the fruity fragrance of fruit snacks, or the sour cream and onion aroma wafting from a freshly opened Pringles can.

Smells can lead us to believe, if not that our junk food isn't manufactured, then at least that it might still contain some nutritional value. And smells can even make food taste nutritious. The Social Issues Research Centre, a non-profit think-tank in Oxford, England, says the nose, not the tongue, is our primary organ of taste--and it can be fooled into tasting certain flavors. Thus, artificial scents have an uncanny way of making things like chips and nuggets taste like nutritious food.

Who are the culprits?

It's tough to find out exactly which stores are pumping out artificial smells, and which food brands use scent additives to mask stale or unnatural food. They don't readily air that information. But a look at the client rosters of companies that craft these smells offers a hint: it's fast food restaurants, hotels, grocery stores, coffee shops, displays, and Disney Parks. Scented packaging is available for everything from cereal, snack, and bread bags to yogurt cups and fruit juice bottles.

One thing's for sure: Our world is increasingly pungent, and our brains are increasingly barraged by the siren calls of smells. But just as rich scents can draw us in, they can also sound a warning. A study published in Flavour Journal found that stronger food smells often cause people to take smaller bites, possibly because we assume the food is more fattening and approach it cautiously. Perhaps our nose isn't so oblivious to our waistline, after all.

Hungry for more? Write to eatandrun@usnews.com with your questions, concerns, and feedback.

Chelsea Bush is a Utah-based journalist on a mission to tap the secrets of psychology to end laziness, cheeseburger addictions, and other annoying habits that keep us flabby. Join the cause here in the comments and at @chelseawriting.