Without our noses, food would have no flavor. And there’s growing evidence that your nose plays a role in everything from how you pick your romantic partners to how nice you are.

That’s according to Avery Gilbert, who wrote a book called What The Nose Knows. And Gilbert should know what he’s talking about. He’s been researching the science of smell for nearly 30 years.

Recently, Gilbert found that small changes in context can drastically affect what we think of a smell. For example, in a recent study, wine experts were asked to rate three different glasses of wine on things like oakiness, fruitiness and smell. Each person gave a different grade to each glass, only to learn that all three glasses contained the exact same wine. The only thing different was the shape of each glass.

Another study asked people to rate various aromas. Volunteers objected to one smell described as “body odor." But when that exact same smell was described as “cheddar cheese,” the sniffers rated it highly.

So how can the context of a smell affect your mood? Psychologists have found that people are more likely to offer help to a stranger if they happen to be standing in a fragrant location like a candy store or a coffee shop. In other words: pleasant smells will literally make you nicer. That’s one reason some furniture store owners now fill their children’s section with the fragrance of bubble gum. They’re hoping the smell puts parents in a better mood, so they’re more likely to spend money!