If you were blindfolded and wearing earplugs, could you follow a chocolate aroma with only your nose to guide you? Research shows, most of us could.
Some of my favourite smells belong to hot things – clothes being ironed, freshly baked bread, paper rolling off a printing press. There is one more favourite but it’s a bit more complex.
Everything from whales to bacteria can smell. Although the human sense of smell is shabby compared to that of many animals, it is still very keen. And women have better senses of smell than men, especially in the first half of their menstrual cycles. An area of your brain the size of a postage stamp can process 10,000 different smells.
You can detect odours even in microscopic quantities. For example, if you put a drop of androstenedione (a compound in human sweat) in an Olympic swimming pool, you can tell the difference between the pool with the drop and the pool without it.
Police in the Netherlands have capitalised on the power of human smell, recently handing out 30,000 scratch 'n' sniff cards, so citizens can tell if their neighbours are growing something they shouldn't be.
Newborn infants locate their mothers’ nipples by smell. And as children grow, they learn to identify many more scents. However, after puberty, your sense of smell deteriorates.
Surprisngly, the human nose is the main organ of taste as well as smell and your smell cells are replaced every 28 days. The tastebuds on our tongues can only distinguish four qualities – sweet, sour, bitter and salt. All other ‘tastes’ are detected by the olfactory receptors in our noses. For example. 'strawberriness' and 'mintiness' rely on the nose, not the tongue. I’m guessing this is why some people with food allergies have reactions even if they only smell the foods they’re allergic to.
Schizophrenics, depressives, migraine sufferers and very-low-weight anorexics often experience deficient or dysfunctional senses of smell. Zinc supplements and acupuncture can sometimes help. Smoking is widely believed to reduce your sense of smell but this is not always the case. On the flipside, blind people do not necessarily have a keener sense of smell than sighted people.
To complicate things further, a smell is not always just a smell. Many stinky substances activate not only the olfactory system but also the ‘somatosensory’ system – the nerve endings in our noses which are sensitive to things like temperature and pain . This is why ‘anosmics’ – people who have completely lost their sense of smell – can still detect scents like menthol.
Your sense of smell is strongly connected to your memory. For instance, the smell of popcorn could remind you of your first kiss at the movies.
Which reminds me of my other favourite smell. Interestingly, I only catch it once in a blue moon. When I attended pre-school, lunch was a picnic made up of everyone’s food shared between all the students. The scent of it was some mixture of peanut butter, celery, bread and fruit. Occasionally, I’ll be walking down a city street and that smell will waft by. I’ll try to pause and catch it but it never lingers. But every time, I am drawn back to being three and learning ‘la vache’ and ‘l'oiseau’, making God’s eyes while someone read to us and painting with powder paint (which has a memorable smell of its own).
So, there you have it. Your nose sits in the middle of your face, quietly going about its business all day, every day. Now, you know what it does.
Your smellprint
Like your fingerprint, how you smell is unique. No two people have the exact same pong. Your smellprint is determined by factors including genes, the environment, diet, medicines, your emotional state, your skin type and even the weather.
Image:
Tina Phillips
