Why smell is the most important sense for our emotions

When he began researching the impact of smell on our lives, scientist Harold McGee had no idea that the biggest pandemic humanity would go through in centuries could jeopardize precisely our ability to smell – and, consequently, taste.

He, who spent the last few decades deepening his knowledge of the relationship between food and science, becoming one of the greatest experts in food chemistry (with research and books published in several countries), began to question how the molecules that enter through the our nose could be so important to understanding the world around us.

The smell of the sea, that pleasure of brewed coffee in the morning that dominates the house, the delicious odor that comes out of the oven telling you there’s cake at grandma’s house. “I started thinking about it in 2007, about how we delve so little into a sense that is able to transport us to such good memories and sensations”, she says.

Something that Covid only made even more relevant, with many people developing symptoms of anosmia when afflicted with the disease. “Not being able to smell aromas left many people shaken. Not least because we didn’t know — and we still don’t know, in fact — the effects of these losses in the medium and long term”, she says.

He started writing the book “Nose Dive – A Field Guide to the World’s Smells” (still no edition in Portuguese) after three years, but it was only published a decade later. “There are few bibliographic references on the subject. To go deeper, I had to do a lot of research”, he explains.

For McGee, it is even surprising that our modern society (especially Western society) has neglected the importance of smell so much. “When we breathe — something we have to do many times a minute — we are absorbing molecules from the world around us. Few senses are more intimate than this one,” she says.

inspire emotions

A study from the University of Utrecht, in the Netherlands, concluded that smell is also the sense that awakens the most emotional memories – according to experts, the proximity between the smell processing center and regions that control emotions and memories in the brain would be the main reason. for that relationship.

“No wonder, during our childhood, when we experience, for example, the smell of food being prepared by our mother, who is a decisive person for our existence, our brain registers this moment and this smell will always be associated with comfort and carefully, with love and safety,” explains McGee.

Conversely, according to him, if we have frightening experiences or in which we are momentarily in danger and there is a predominant smell in the environment, this aroma will be a negative trigger and feeling it will always cause us great discomfort. “For me, who live in California, the smell of wood burning was always very comforting, as it reminded me of the heat of the fireplace on the coldest days”, he says.

But since fires raged across the state in recent years, that smell has taken on a whole different meaning for the scientist. “I can barely feel it, I’m paralyzed,” he says. “Our brain is constantly perceiving what is happening in the world around us, interpreting and making associations based on the experiences we accumulate. Smell is an important ally for our mind to organize them”, he details.

In our evolutionary history, smells have helped us preserve our existence by allowing us to perceive the dangers we might encounter—whether it was in spoiled food or even in the presence of a predator and a leaking gas cylinder. But with the technologies, we were putting aside this instinct (which we sometimes started to disguise with fragrances and perfumes to cover the natural smells) and paying more attention to others.

The development of music, the arts, literature and even gastronomy are proof of how other of our senses (such as sight, hearing and taste) have gained greater importance among us. “Smell became a secondary sense,” he says.

Smell that invades us

In a nutshell, smells, he explains, are volatile compounds that come off things and enter our body, accessing our brain. When we leaf through a book, for example, a variety of wood pulp and paper fibers come off the pages to enter our nostrils.

As breathing is a physiological act and therefore mandatory, we can’t help but smell things — good and bad, of course. But as it is also an automatic act, we do not always pay as much attention to these odors that invade us. “We are only attracted to perfumes and fragrances, when the smell, in fact, is a key to understanding what is around us, from affective relationships to the pleasures of the table”, he explains.

In this sense, by the way, the flavor itself has in the aromas a fundamental component for its perception. Taste itself is what happens on our tongue and involves few sensations: sweet, sour, bitter, umami, salty and so on. But there is no “taste” without taking into account what goes on in our nose.

“And there, the number of possible sensations is tremendous. There are tens of thousands of combinations that the smell adds to the taste, because it represents many more possibilities”, he explains. Coffee, for example, can have 800 volatile molecules of different aromas after roasting.

“The reason smell is so powerful is that it’s our bridge between what’s happening on our tongues as we eat and what’s out in the world. Our brain is constantly comparing what we have in our mouths with what it knows about. what is out there, creating a very rich database”, he details.

That’s why sommeliers, chefs and other food professionals insist on the importance of aromas. Feeling them even before eating can open up new insights into the plate of food or wine we are willing to taste.

“Controlled” scents

According to McGee, the recent appreciation of the sense of smell began, however, before the pandemic. He believes this is a direct consequence of industrialization and urbanization processes, which standardized smells under the argument that they would be better for us, representing better hygiene and comfort — from the odor of disinfectant (always between pine and citrus) to comforting smells. , like the tutti-fruti that reminds us of childhood or the sweet herb in the soaps with which we usually wash our hands. “The ‘controlled’ smells gave us a sense of security,” he says.

But the rescue of fermented foods (from sauces like garum to pickles) and a recent appreciation of artisanal cheeses and wines without intervention and with all their natural aromas are examples of how people are more open and curious about real smells — especially if they’re strong and poignant, something we’ve historically learned to split.

For the book process, McGee says he developed his sense of smell with the help of tobacco (which he doesn’t smoke, but which has always intrigued him). “From the smoke to the fermented leaves, the aroma nuances are many and very rich. When a person smokes, there are many molecules shared, not only in the smoke, but in the leaf itself”, he analyzes.

For the scientist, we tend to create a better relationship with our surroundings if we can interpret it from its many smells. His tip is to pay attention to the aromas that surprise us throughout the day. “I have no doubt that, especially after Covid-19, we are rediscovering the wide range of aromatic possibilities we can enjoy and the value they have for our emotions,” he concludes. Pleasures that are literally right before our noses.