“A man eats nothing without smelling it more or less consciously, while with unknown foods his nose acts always as the first sentinel, crying out Who goes there? When the sense of smell is cut off, taste itself is paralyzed...”
― Brillat-Savarin JA. in ‘The philosopher in the kitchen/the physiology of taste’, 1835
“How fortunate we are to be food-consuming animals. Every meal should be a treat and one ought to bless every day which brings with it a good digestion and the precious gift of hunger.”
― Charles Arrowby in Iris Murdoch’s ‘The Sea, the Sea’, 1978
Most of us have experienced the muting of flavours that come with a common cold. As your synesis grow heavy and congested, breathing becomes laboured and stripped of the joy and utility of smell. The life seems to slip from meals like colour draining away from a cartoon.
In early November of 2020, I contracted COVID. Overall, I didn’t feel that unwell, spending a week on the sofa in a hazy state as Joe Biden pushed Donald Trump out of office. My most distressing symptom was the steady dismantling of my sense of smell and taste. Over the week, I lost the ability to detect any information about the food I was putting in my mouth. I could have chomped on a raw onion or sucked the juice from a lemon and the flavour experience would have been the same. Without smell or taste, food didn't summon the usual rush of saliva, leaving my mouth dumb and unresponsive. There was satisfaction still in a crunch, in the combination of bite and something silky soft. But most foods were rendered foreign objects in my mouth - fibre, mush and liquid that I wanted to swallow down as quickly as possible.
To understand this phenomenon, let’s take a quick anatomy lesson. The experience of flavour is a collaboration between two distinct processes: taste and smell. Taste describes how the pores on your tongue detect saltiness, sweetness, bitterness, sourness, and savouriness or umami. These are the building blocks of flavour - components that when in balance create depth and satisfaction in food, and form a base for the top notes of aroma and complex flavours. Smell is the detection of odour molecules by cells in your nose. The lining of the nasal cavity is covered with tiny hair-like protrusions, called cilia, which are connected to nerve cells. These transmit information to your brain, which in turn creates a sensory experience.
Smell is generally considered to be the dominant force: around 80% of the experience of flavour is derived from smell. This may seem counterintuitive, as we don't need to actively sniff our food to enjoy the flavour, but this is because the nose and throat are connected. As we chew a mouthful of food, aromas travel through the back of the mouth and reach the cilia.
COVID, among other things, can cause a range of issues with the olfactory system. The total loss of smell, experienced by many in the early stages of COVID, is called anosmia. A loss of the sense of taste is called ageusia. These can be caused by damage to the cells that detect smell and taste, or to the neurons in the brain that interpret this sensory information. The current scientific understanding is that COVID launches a direct attack on the tissue in your nose and the taste pores of your tongue. It causes inflammation and damage that inhibit the nerve cells from doing their job and can kill them off entirely.
I didn’t know that this was happening in my body at the time, I merely noticed the curious effects. But stranger - and more disturbing - still, was what happened as I recovered. Slowly over Christmas and New Year, my sense of smell and taste returned. I enjoyed mince pies and mulled wine, albeit with a slightly dulled palate. But in late January, three months after I had COVID, I was brushing my teeth when I noticed an off smell, like something rotten. I smelt the same bad smell the next day, when I chopped into an onion.
It took me a few days to figure out, but I was suffering from parosmia. It’s a condition that causes the misperception of a smell - when your brain’s reading of a familiar scent becomes distorted. Usually, it distorts in an unpleasant way. Turning to Google to make sense of it, I found a tidal wave of new cases of parosmia following in the wake of COVID.
Over the following weeks, the list of foods that would trigger this ‘bad smell’ grew: mint and onion, but also garlic and ginger, bananas and citrus fruit, wine and most soft drinks. The list wasn’t limited to foodstuffs - cosmetics could also set it off. My sensitivity to these smells was heightened. I could tell one of my neighbours was chopping onions just by opening my kitchen window. The smell itself is hard to describe. Its defining characteristic is the avoidant feeling it triggers, but it could be compared to compost heaps, rotting drains or animal waste. A smell that conveys the message: don’t touch or eat this
Parosmia has become a common-known sequela of COVID, some studies have estimated that around 40% of those who experience anosmia during COVID will develop parosmia. It typically occurs three months after infection when the nerve cells begin to regenerate. During the healing process, these cells can misconnect or misfire, triggering a scrambled signal to be sent to the brain. One theory is that when your brain can no longer recognise a once familiar smell, it defaults to a warning setting - we don't know what this is, it may do you harm, best to avoid it for now.
I am in agreement with Iris Murdoch's character Charles Arrowby in her novel ‘The Sea, the Sea’: every meal is an opportunity for pleasure, a blessing to be gratefully received and savoured. I love to cook, but more than anything I love to eat. Discovering new flavour combinations feels like finding a ten-pound note on the ground - a rush of luck and joy and new possibilities. While familiar foods are one of the greatest sources of comfort I have found. Smell and flavour are powerful triggers for memory that we feel deep in our bodies. Food can transport you to the past: conjuring memories of family meals, childhood holidays, and feelings of being cared and provided for.
It took a year for my nerves to heal and for foods to no longer trigger the bad smell. It was a year of compromise in the way I cooked and ate, and of disconnection from the joy of food. Today, more than two years later, I feel like I experience the smell and taste of foods as I did before. But smell memories are blind - there are no photos to refer to. Perhaps I have just gotten used to the new aromas. Like my mother, who didn't realise that her perception of white had become yellow until she had surgery for cataracts.
What remains is a lack of trust in my own perception. Like the philosophical thought experiment: how do I know that the blue I see is the blue you see? We can't know whether or not we experience the smell of caramelising onions or freshly brewed coffee in the same way. While we are generally in agreement about what are good and bad smells, I wonder how much of this perception is learned - the power of suggestion or positive association. The pleasure of a particular smell builds over time, as we learn that wine will relax us, or we fall in love with a person and the smell of their skin at the same time. These bodily responses are emotional. Perhaps I needed to rebuild positive associations before these smells could be pleasurable again.
There are moments that add strength to my doubts - when I don't seem to experience a smell in the same way as others, or when I catch a cold and the bad smell of parosmia returns. It is still present in my body. It's a sad feeling for someone who loves to cook. I've lost confidence in my ability to judge a dish or pick up on nuances of flavour. But it's also given me a deep appreciation for the fact that I can taste and smell at all and that I am, as Arrowby says, a food-consuming animal. I’ll continue to count myself lucky for each day that brings the opportunity of three meals, and the precious gift of hunger.