Your Sense of Smell: More Important Than You Think

Some might say that a sense of smell is the least important of the five senses, but smell actually affects our lives in some dramatic and unexpected ways. Smell receptors are directly connected to our brains, so when a scent hits our noses, the information is immediately sent to our brains.

Sense of Smell and Memory

The part of the brain that processes smell is also responsible for memory and emotions. This is why smells can trigger early childhood memories that may have been long forgotten. Have you ever caught a whiff of pipe smoke and not only pictured your uncle reading the paper and smoking his pipe, but remembered the warm feelings you had for him? Does the smell of cinnamon cookies baking bring back memories of your grandmother's kitchen and her comforting hugs? For me, the scent of slightly mildewed old books instantly transports me back to the small rooms of the county library that I loved when I was nine years old and the lovely librarian who gave me "The Secret Garden" to read.

We all know that food tastes bland when we have stuffy noses due to a cold, but did you know that 80% of your sense of taste is smelling it? Imagine how much we'd miss if we couldn't smell that baking bread, cheesy lasagna or grilled steak.

Our sense of smell becomes less acute as we age, partly because it is dulled and partly because we just become so used to certain smells that they no longer register individually.This explains why older people complain that food no longer tastes good and why they may over-season food.

Infants Develop Sense of Smell in Womb

Scientists believe that babies can already smell while in the womb. By the time a woman is thirteen weeks pregnant, the olfactory (nose) nerves are connected to receptors in the brain. Babies can actually identify a variety of smells in the amniotic fluid before birth. After birth, infants can identify the unique scent of their mother's amniotic fluid. A few hours after birth babies can identify their mother's scent and the scent of their mother's breast milk. Because babies are comforted by breastfeeding and by the smell of their mothers, it's possible that a small amount of breast milk expressed on their blanket will comfort them when their mother isn't around.

These definitions were found in Wikipedia:

Anosmia (pronounced /ænˈɒzmiə/) is the inability to perceive odor, or in other words a lack of functioning olfaction.

Olfaction or olfactory perception is the sense of smell. This sense is mediated by specialized sensory cells of the nasal cavity of vertebrates.

Pheromone (from Greek φέρω phero "to bear" and hormone, from Greek ὁρμή "impetus") is a secreted or excreted chemical factor that triggers a social response in members of the same species.

While it has long been known that animals can smell fear, recent studies in the European Journal of Personality (Sorokoska et al.) have shown that people can sniff out dominance, extroversion and neuroticism in sweat. Women seem to have a better sense of smell in this area and are particularly accurate in identifying dominance in men by smelling their sweaty t-shirts.

Surprisingly, happiness can also be detected by smelling sweat says an article in Psychological Science (de Groot et al., 2015). Although test subjects did not consciously recognize the smell of happiness, videos of women smelling "happy sweat" show that their facial muscles relax into a smile, similar to one's reaction to another person smiling.

There are the obvious people smells that we can all identify. The tropical flower perfume of our best friend, the Lily of the Valley dusting powder that Aunt Maggie uses, or the Old Spice that clings to grandpa will evoke specific images of that person. But did you know that our sense of smell is connected to our romantic attraction to certain people?

Pheromones

Many animals identify and are attracted to potential mates by unique chemical scents called pheromones,and it turns out that humans are no exception. Until the 1980s it was thought that humans did not smell pheromones, but then a team of scientists led by Luis Monti-Bloch of the University of Utah found the tiny pair of pits inside the nose that are lined with receptor cells triggered by pheromones. While people don't consciously smell pheromones, they do have a response to them.

Opposite Smells Attract

It turns out that the old saying, "Opposites attract," has a basis in truth as women are attracted to men whose pheromones have dissimilar chemical makeup from their own.

While pheromones are not obviously noticeable, we smell them all the same, and that's one reason we're attracted to some people and not attracted to others. Studies have shown that women are unconsciously attracted to men whose body scents are most dissimilar to their own. Scientists believe that this is a way of ensuring better genetic compatibility and immune systems in their possible offspring. However, during studies, it was discovered that women on birth control pills were attracted to males with similar scents because their bodies thought they were already pregnant.

Short Circuiting Natural Selection?

Now, here's something to think about: Are we short circuiting the natural functions of our sense of smell for selecting the best mates by perfuming, showing, deodorizing and taking birth control pills? Should women use other methods of birth control when looking for a mate...maybe at the YMCA gym? Hmmm....

It's even been suggested that women who enter into a relationship while on birth control pills may become disenchanted with their choice once they no longer use the pill.

The loss of your sense of smell, or anosmia, can be a precursor to other, more serious, problems.

Loss of smell not only affects your ability to taste the subtle flavors of food, it is also connected to your memory. Dr. Richard Doty, of the Smell and Taste Center at the University of Pennsylvania, says that loss of smell is one of the initial symptoms of neurological diseases such as Parkinson’s and Alzheimer's. Studies have shown that here is a big connection between lowered sense of smell and the likelihood that a person will develop these diseases later in life. He theorizes that, in some cases, environmental factors could be responsible for loss of the sense of smell and that those harmful toxins eventually cause Parkinson’s and Alzheimer’s.

For more in depth reading on the effects of Anosmia, check out Annette R. Smith's article, Anosmia: When Your Nose Doesn't Know.

Viruses and respiratory illness can affect our sense of smell, and because of that COVID-19 (SARS-CoV-2) had a profound effect on olfactory senses as loss of smell was an early indicator of the disease. Although not everyone who contracted COVID-19 lost their sense of smell, some lost it entirely. Sometimes this was a temporary symptom of the illness, others suffered for months or longer. It also changed the way the brain processed smell as sometimes previously pleasant smells were perceived as repulsive. Because of the huge number of people who contracted COVID-19, scientists have learned much about how viruses attack our olfactory senses and have proposed new ways to treat the problem.

Here are some random, but interesting facts about smell:

• The average person can recognize about 10,000 different smells!
• People can recall smells with 65% accuracy after a year, but visual recall is only 50% accurate after 3 months.
• Odors have a strong connection to memory because the part of the brain related to olfaction (smell) also handles memories and emotion.
• Our sense of smell is responsible for 80% of what we taste. When our sense of smell is blocked our sense of taste is drastically reduced.Our sense of smell is strongly related to emotions, and very suggestible. If we are told that there is a certain smell in the room, chances are we will begin to smell it.
• Our sense of smell is fully developed at birth, and before!
• The global market for fragrances and perfumes is estimated to reach $33 billion dollars in the next two years.
• The perfume industry and whale vomit. Whale vomit is called ambergris. It smells like fungus or wood and pieces of it are sometimes found washed up on beaches. Sound like you wouldn't want to pick this up? Think again because ambergris is floating gold! In 2006 an Australian couple found a piece of whale vomit that they sold for $295,000! In case you’re wondering what makes it so valuable, it is used as a stabilizer in making fine perfumes like Channel No. 5.

Aromatherapy uses scents derived from natural plan extracts and oils. Some aromas have health benefits and can even affect us physiologically. Research has shown that certain odors can help relieve stress, anxiety and depression. While the field of aromatherapy is very broad, these are a few of the scents that have proven effects on us:

• A lemon scent will significantly increase people's perception of their own health.
• Lavender incense contributes to a pleasant mood—but it lowers volunteers' mathematical abilities.
• The scent of lavender and eucalyptus increases people's respiratory rate and alertness.
• The scent of phenethyl alcohol(a constituent of rose oil) reduces blood pressure.

There are some excellent in-depth articles on the use of aromatherapy and its health benefits. See some suggested links at right.

We all appreciate the smell of good food cooking or a bouquet of fresh flowers or a freshly bathed baby. But when you stop to think about it, there is so much more to our sense of smell.

And if you are a woman and have connected to the perfect mate, perhaps you have your sense of smell to thank!

--------------------------------------------------------------------------------------------------------------

Copyright ©2013 Stephanie Henkel