Remember the last time you felt miserable in a stinky cab or were tempted by the smell of freshly baked cookies in a cake shop? Odours and scents can totally change our impression of the world.
Most of what we smell is involuntary: we have little control over the smell of garbage in the streets or the smell of popcorn in a movie theatre. But what if we could train our nose to pick out scents on purpose? What if we could tell the “bouquet” of any wine in the world or pick out all the notes in any perfume on earth just by the power of our nostrils?
The nose, it turns out, is immensely trainable. The late Helen Keller, who could neither see nor hear, had also developed her sense of smell to such a degree that she could tell if the person standing next to her was a carpenter, an artist, a mason or a chemist!
When we get a whiff of something – say, a buttery crepe – what we’re receiving is the odour molecules from the butter, flour and filling floating through the air. These molecules reach the nostrils and dissolve in the mucus on the roof of each nostril.
Beneath the mucus is a sheath of the olfactory epithelium which contains specialized receptor cells called olfactory receptors, which detect the odour. These receptors have the ability to detect thousands of different odours.
The olfactory receptors then transmit the odour signals to the olfactory bulbs, which are located at the back of the nose.
The olfactory bulbs transfer these odour signals to various parts of the brain like the piriform cortex, thalamus, amygdala and hippocampus. These brain centres perceive odours and access memories to remind us about the people, places, or events we associate with those smells to determine whether you like the smell or not.
Think of it like Lego blocks: there are recesses (in this case, smell receptors). The new pieces (odour molecules) go in and click into place to make a smell that the brain can perceive. Your brain then goes through your entire catalogue of memories: so if you had an unhappy incident in a movie theatre as a child, you might hate the smell of popcorn. Or if some of your happiest memories have to do with road trips or freshly dry-cleaned clothes, you might love the smell of petrol.
5 easy ways to improve your sense of smell
Food would taste bland if we couldn’t smell it. The sad truth is that our sense of smell and taste declines with age. The good news: there are ways to counteract this to an extent. Here are five science-backed ways you can try to improve your sense of smell:
1. Smell different things
The more you use your senses, the better they get. Getting close to the source makes it easier for your nose to perceive the smell. To learn more about scents, smell aromatic things around you: herbs, teas, coffees, chocolate, olive oil, mangoes piled up in a grocery store.
Try this: the next time you’re drinking whisky or if you are about to bite into cheese, take time to really breathe in the smell before you consume it. We promise it will taste more delicious, in addition to making your sense of smell keener.
2. Sniff a bit more
Studies have shown that sniffing for just a bit longer can intensify your brain’s information-processing ability and help to recognise smells. Also, when you smell for a longer time, you tend to inhale more odour molecules, which may help in getting a better perception of the smell.
3. Build your scent IQ
It takes years of training to become a master sommelier, perfumer or pick out fragrant leaves at a tea auction in Kolkata. But anyone can improve their “scent IQ” by simply sniffing their surroundings.
Research carried out at the University of Dresden’s Smell and Taste Clinic in Germany found that a person can enhance their olfactory bulbs with training. The researchers added that people with an average sense of smell can increase the size of their olfactory bulbs with a regimen of trying out four aromas, twice a day, for about 30 seconds each.
Try this: begin by simply choosing four smells that you are fond of, such as fresh coffee, bananas, soap or shampoo and cheese. Then each day, take two minutes to go through and smell each one individually to stimulate the receptors inside your nose.
Try to repeat this at least four times a day for a week and then switch to other smells.
4. Supplement your power to smell
Partial or complete loss of smell can be a symptom of vitamin B12 deficiency. Eat fish, meat, eggs, and dairy products like cheese, milk, yoghurt to get your fill of B12. Don’t forget to sniff these foods before eating them.
5. Quit smoking
According to Dr Andrew Spielman, professor of basic science and craniofacial biology at the NYU College of Dentistry, US, smokers can’t appreciate the taste of many foods as intensely as they did before they started smoking because smoking destroys their sense of smell, which eventually depletes their ability to taste.
For more information, please read our article on Vitamin B12 Deficiency.
Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.