In the winter of 1994, I stayed with my grandmother for a couple of weeks while my aunt, her full-time carer, was travelling. It wasn’t an imposition. I’d lived with my grandparents until I was eight years old, so to be back in that dim but beloved house was like revisiting my childhood. At the end of each night, in peak grandmother-mode, my gran would send me off to bed with a hand-crocheted blanket and a cup of hot chocolate.

A week or so into my stay, I woke up feeling dreadful. My head was pounding, my gut was roiling and I felt as if I’d barely slept. Although I was in my mid-twenties, this wasn’t a hangover. The highlights of the previous night had been watching Murder, She Wrote and that cup of hot chocolate.

In the kitchen, Gran looked similarly secondhand as she drooped over the newspaper crossword, black smudges of exhaustion visible behind her glasses. She offered to make me a coffee, but I waved her back to her chair. My regular hit of long black was the last thing I wanted with my queasy gut and fussing with my stovetop percolator felt like too much effort. A cup of tea was about all I had the stomach or energy for. And (tea-drinkers of the world forgive me), I slung a teabag into a mug of cold water and shoved it in the microwave.

The doorbell rang. My boyfriend was on the doorstep, ready to collect me for work. As I swung open the heavy front door, he took a single breath and yanked me away from the house. Then he dashed back inside. Seconds later, he was hustling my dressing-gowned gran to join me on the footpath.

The previous night, after making me that cup of hot chocolate, Gran had accidentally left the stove on. All through the small hours, gas seeped into every room. When I opened the front door to greet my new love, a wave of vapour billowed out, the smell overpowering his nose. Had I not been so dazed and debilitated by the fumes, it’s likely I would have made myself a coffee – and at the moment of stovetop ignition, killed myself and my grandmother in a Michael Bay-worthy suburban explosion.

That lazy cup of microwaved tea saved both our lives.

Anosmia: an inability to smell

My gran and I shared something else besides a love of hot chocolate. Neither of us could smell the gas filling the house. We have congenital anosmia; neither of us have ever had a sense of smell.

Anosmia is far more common than most people think. Anosmia and hyposmia, the inability or decreased ability to smell, is estimated to afflict between 3% and 20% of the population, including loss of smell from either a brain injury or a nasal condition. Or, like Gran and me, they are anosmic from birth.

When it comes to sensory deficit, anosmia can’t compete with being blind or deaf. Yet in many ways, smell is a fundamental element of the human experience. As my gran and I can attest, to live without a sense of smell is dangerous. Smoke, gas and spoiled food are all undetectable to people like us, which poses obvious risks to our safety.

But beyond that, smell is vital to quality of life. So much of the succulence of human experience comes to us through scent. The senses of smell and taste are so intertwined that losing the ability to smell seriously diminishes your appreciation of food and drink.

While our taste buds still detect the basic distinctions between foods that are salty, sweet, bitter or sour, the enormous variety and subtlety of flavours and aromas that come to us through airborne, volatile chemical particles are lost when we lose the ability to smell.

For those born with a sense of smell, only to lose it, the impact is severe.

Loss of smell is associated with substantially increased rates of depression, anxiety and reduced quality of life. Over the long term, people who can no longer smell face challenges with loneliness, maintaining personal hygiene and social relationships.

But one of the saddest aspects of losing your sense of smell is losing your connection to the profound array of memories and associations that can be triggered by scent. Helen Keller, the deaf and blind author and political activist, said “smell [is] a potent wizard that transports us across thousands of miles and all the years we have lived”.

This curious association between scent and memory has a physiological basis. Within the brain, sight and sound are processed by the neocortex, while smell is processed by the limbic system: an ancient structure that also deals with memory and emotion. This explains why smell can so formidably awaken emotional memories. Think of Proust’s famous scene in Swann’s Way, dipping his madeleine into a cup of tea and the scent of it immediately transporting him back to his childhood.

Whenever this now common literary device is used, I must admit to feeling a touch of melancholy. Proust’s story will never land for me the way it does for other readers, and it makes me aware of the shortcut to memory and nostalgia that will always remain a hidden path.

I live in the Adelaide Hills and when I began writing poetry, my early work focused on the beauty of the natural world. Yet there was always something missing; my poems felt more like postcards of landscapes than three-dimensional ecosystems. Finally, the penny dropped. I was perceiving my surroundings and trying to write about them based on only two of the five senses: sight and hearing.

In many ways, reading about the fragrant elements of the world makes me feel like an anthropologist studying a different culture, or a traveller reading a guide to a country I’ve never visited.

When the pandemic hit in 2020, millions of people entered the sensory world I’d inhabited my entire life: smell and taste dysfunction were........

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