This is going to sound weird, but I want you to look closely for a moment at your thumbs. See how they flex forwards as well as back. Notice how responsive and grippy the skin is. The human thumb is not just a device for giving the thumbs-up sign or for picking up dropped keys. It is also one of the most efficient and sensitive tools in existence for determining the ripeness of fruit.
One of the hallmarks of being a hominid is having opposable thumbs: stronger, longer and more flexible than the thumbless hands of a spider monkey or the non-opposable thumbs of a marmoset. These opposable thumbs are a trait that humans share with our primate cousins such as chimpanzees. But it has only recently been discovered that our thumbs might have first evolved as a device for measuring whether or not fruit was ripe. In 2016, biologist Nathaniel Dominy studied the way chimpanzees pick figs. Dominy found that chimpanzees use their dexterous hands to give figs a quick squeeze to determine whether they are ripe or not – a technique that works four times quicker on average than the method used by monkeys (plucking figs at random, biting them to check for ripeness and spitting out the unripe ones).
Humans also have these incredible hands capable of identifying the ripest fruit from touch alone. But most of us don’t use them that way any more. If you want ripe fruit, you no longer need to rely on your own sense of touch. You can go into the nearest supermarket and buy a plastic tub of pre-peeled, pre-sliced mango or melon labelled “ripe and ready” or “ripe and sweet” and eat it with a fork.
One of the most striking things about eating in the modern world is that we do so much of it as if we were sense-blind. We still have the same basic physiognomy as our hunter-gatherer ancestors, yet much of the time, we switch off our senses when choosing what to eat. Our noses can distinguish fresh milk from sour milk, and yet we prefer to look at the use-by date rather than sniffing. Senses, wrote the late anthropologist Jack Goody, are “our windows on the world” – the main tools through which humans acquire information about our environments. Senses are instruments of survival as well as pleasure. But today, we have relinquished many of the functions of our own senses to the modern food industry – which suits that industry just fine. It suits us less well, judging by the current epidemic of diet-related ill health.
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The pandemic revealed what a blind spot our culture has about our own senses, especially our sense of smell. Never before has the loss of a human sense happened so fast, in so many places at once, as the anosmia (smell loss) caused by Covid-19. But perhaps the most noticeable aspect of this mass anosmia is that we lost something that many of us had forgotten we even needed. A sense of smell has long been regarded as something trivial and even inessential to humans (as opposed to other animals, such as dogs, who live by their noses). Charles Darwin was among the scientists and philosophers to argue that a sense of smell was of “extremely slight service” to humans (compared with the senses of vision and hearing). A survey of 7,000 young people in 2011 found that most of them would be hypothetically prepared to give up their sense of smell if it meant that they could keep their laptop or phone.
In reality, it is not easy to live without a sense of smell. We know from survey data produced by the charity Fifth Sense that anosmia lessens enjoyment of food and drink for almost everyone, as well as increasing feelings of loneliness and depression and in some cases leading to the breakdown of relationships. The Fifth Sense survey of nearly 500 anosmia sufferers found that 92% reported enjoying food and drink less than they had when they still had a functioning sense of smell. More than half of the respondents said that they went to restaurants less often than before, and they also reported that cooking had become a source of stress and anxiety because they could no longer experience the joy of trying new recipes, and could not easily tell when something was burned. One Fifth Sense member reported that they missed both the “dangers and delight” of being able to discern the various odours of food. I felt bereft when I came down with Covid in September 2021 and discovered one morning that my usual cup of coffee had lost all its aroma. I sipped in disbelief, waiting for the perfume to return, but all I got was the jolt of caffeine and bitterness on my tongue.
Photograph: Wirestock, Inc./Alamy
From the data so far, it seems that the vast majority of those who lose their sense of smell owing to Covid-19 will achieve a full recovery within a few weeks. I was among this fortunate majority. One day, I zested a lemon and practically cried with gratitude when I noticed the brightness of citrus in the air. But a small percentage of those affected by post-Covid smell loss will never get it back. A 2020 paper analysing the self-reported experiences of long Covid sufferers on a Facebook group gave a sense of how the joy gets sucked out of food for those who can’t smell. Some said that they lost their appetite while others had the opposite reaction, desperately eating more in an attempt to compensate for the loss of pleasure. One person noted that “food satisfaction is lacking and I see myself eating more just to try to get that satisfied feeling … I am gaining weight due to a constant urge to satisfy what can never be satisfied”.
Given the sheer number of people around the world who have suffered from the virus, it seems likely that tens of thousands will be left living with permanent anosmia, or parosmia, a related condition in which those affected are tormented by horrible false smells such as burning rubber. Yet before 2020, very few people even knew the word anosmia, let alone realised it might be something significant for their wellbeing.
Our ignorance about anosmia is part of a wider loss of engagement with our own senses in relation to food. No human activity is more multi-sensory than eating, but to eat in the modern world is often to eat in a state of profound sensory disconnect. We order groceries on a computer, or takeaways on a phone, and they arrive wrapped in plastic, so that we can neither smell them nor see them before we take the first mouthful. Vegetables are sold prechopped and almost all salad is prewashed. Any hint of the soil the food grew in has been erased. We judge the goodness of food by the words on the packet rather than by our own senses. In the US and UK, more than half of all calories consumed are made up of ultra-processed foods whose ingredients are so heavily disguised that they are beyond the power of human senses to disentangle. Very likely, we then eat this meal in front of a screen, barely glancing down to see the colours or shapes of what we are consuming.
Our sensory disconnect from food is both cause and consequence of the fact that so many of us have poor diets. This starts early. Consider commercial baby food. Much of this is now sold as disposable pouches of pureed fruits and vegetables in which the colours and shapes of the original food are hidden. Parents like these pouches – which often boast that their contents are organic – because they are a convenient way to feed a baby or toddler while out of the home. But as a report from the First Steps Nutrition Trust highlighted in 2018, these pouches are not a good way for babies to get their first exposure to food. By sucking food directly from pouch to mouth (which seems to be how they are generally used, even if the manufacturers officially say that they recommend decanting the product into a bowl), children cannot tell what they are eating. Why does this matter? Dr Helen Crawley, a public health nutritionist, has noted that eating purees from a pouch does not help children to get accustomed to the tastes and textures of real food. The problem is that a pouch of sweet carrot gloop does not teach a person either to enjoy or to recognise real carrots.
I first became aware of the extent to which a sensory disconnect from fresh food has become normal when I started conducting taste education sessions with children in British schools a few years ago. I am one of the founders of an organisation called TastEd – short for taste education. TastEd – which is based on the Sapere method used in France, the Nordic countries and the Netherlands – involves bringing fresh vegetables and fruits into the classroom and getting children to use all of their senses to interact with them. The programme, which is now taught by nursery and primary teachers in more than 160 schools in England, consists of a range of free teaching materials designed to help children to get to know basic foodstuffs by touching, smelling, listening and looking at them, as well as eventually tasting.
A mango festival in Sydney, Australia. Photograph: Brendon Thorne/Getty Images for Australian Mangoes
Some would argue that this kind of sensory food education in school is superfluous. Don’t children learn this stuff at home? But apparently they don’t, or at least nothing like as much as they did in the past. Some parents are forced to work such long hours that they hardly get the chance to share family meals with their children. Many others are on such squeezed incomes that fresh food can be more or less unaffordable. For families of all incomes in the west, there is an additional cultural problem, which is that it is not seen as normal for children to enjoy fresh vegetables. Whatever the reason, the average child now seems to have a very limited sensory literacy of food. In 2010, the TV show Jamie Oliver’s Food Revolution showed American children in West Virginia who believed that tomatoes were potatoes and who said that an aubergine was a pear. At the time, I recall hearing people commenting that the children’s ignorance was symptomatic of living in West Virginia. In fact, you will now find children all over Britain with a similar lack of food knowledge.
A few summers ago, while I was first trialling the lessons alongside a reception class teacher in Cambridge, it was peach season and I bought some delicious flat peaches to share with a class of four- and five-year-olds. One boy leaned forwards and said: “I’ve never touched a peach before, but I’ve had peach-flavoured medicine.” This boy had never known the fuzzy sensation of peach skin on his hand or in his mouth, or the quiet squelching noise a peach makes when you bite into it. This wasn’t unusual. The following summer I brought peaches into another classroom, this time with year 4 classes. One nine-year-old girl stared blankly at the fruit and told me she was surprised real peaches didn’t look more like the peach emoji.
Since then, we’ve met 10-year-old children who have never tasted a carrot or a raw tomato, and who have no idea what it feels like to hold an onion or a potato. There are children who could name every football team in the Premier League in the correct order but don’t know that cherries come with stones inside, because they have never seen anyone eating one, never mind tried one for themselves. Teachers have told us about children who smelled a fresh mint leaf and the only thing it reminded them of was chewing gum and mint-scented shampoo.
Jason O’Rourke, the head teacher of Washingborough Academy in Lincolnshire and one of the founders of TastEd, has told me that when asked where food comes from, children at his school used to say “from the supermarket”. Now they say “from Mummy’s iPad”. The deep ignorance that children have about food is part of something much bigger: a global food system in which the chains of distribution are so long and impersonal that very few of us – adults or children – have any connection with the people who grew or reared what we eat.
The sensory disconnect of modern life didn’t happen all at once. We are living at the endpoint of many centuries of sensory disengagement from our food. Although the idea of the five senses is near-universal across human societies, each culture has its own ways of conceptualising those senses. The cultures in which sensory knowledge of food – particularly through smell – are most vivid are hunter-gatherer communities.
When most humans were hunter-gatherers, no one could afford to eat with their senses switched off. You needed to be able to sniff out the difference between a poisonous berry and a sweet one, and to listen alertly for the footsteps of wild game. For hunter-gatherers, senses are survival. This became less urgent with the adoption of farming in the neolithic period. Suddenly, not everyone in the community was responsible for foraging or hunting their own food, because we could rely on farmers to supply us with grain.
Anthropologists have found that as societies modernise, one of the common patterns is that the sense of smell becomes less important and the sense of sight becomes more so. Asifa Majid, a professor of psychology at the University of York and a leading expert on olfactory language, has said that smell used to be considered a “mute sense” compared with sight because English speakers have far fewer words for describing smells than they do for colours.
But Majid’s field work has shown that for certain hunter-gatherer communities, smells can be named as easily as colours. Among the nomadic Seri community in Mexico for example, speakers have different words to distinguish between the specific smell of sea lion, the smell of spoiled beans, the smell of burned beans, the smell of cooking immature green sea turtle and the smell of rancid honey. For the Seri, this rich smellscape is a crucial part of everyday life. By contrast, someone living in London or New York today might smell the burned beans just as potently as the Seri, but have no word for the particular way it smelled beyond “yuck”.
As Majid writes: “In English, a stink is a stink is a stink.” We sometimes make fun of wine writers for describing the perfume of different wines in such pretentious terms (“a bouquet of liquorice” or “topnotes of gooseberry”), but similes are often the only way we can describe smells with any precision in English because our odour vocabulary is so limited.
Long after the decline of hunter-gathering, however, selecting food continued to be deeply sensual. The historian Madeleine Ferrières has described the order in which a buyer would traditionally use his or her senses when buying food at a medieval food market in France. The first task was to smell, because it was common knowledge that “everything that stinks, kills”. Next came close looking, to confirm that the food really was as fresh as it seemed. The next sense was touch, taking the food in the hand to gauge its weight and assess its quality. Finally, a buyer might taste a little of the food to determine whether the produce really was fit to eat. In the French civil code, consumers had a right to touch and taste a sample of the food before they committed to buying it.
A sensory approach to food shopping continues to be normal to some degree wherever there are open-air food markets. Traditionally, to test whether a watermelon was ripe, Chinese consumers would tap on it. Ripe melons make a hollow sound. In the UK we used to do something similar with a variety of apples called Cox’s Orange Pippin. You would shake the apple, and if it was ripe the seeds would make a gentle rattling sound.
Now we have largely lost the sensory experience of handling food when we buy it. All over the world, open-air markets are being supplanted by supermarket shopping. The seductive promise of the supermarket is that it will do most of the job of hunting and gathering for you. All of the produce for sale in these vast cathedrals of commerce has already been vetted and packaged and labelled and then assembled under one roof by someone else for your convenience, so that you can focus your time and energy on other things.
I will never forget how ecstatic my mother was on her trips to the first big Sainsbury’s in our town in the early 1980s. This anonymous and well-stocked marketplace spared her – a working parent – the bother of traipsing between separate markets and shops such as grocers and bakers as she had previously done. One of the tradeoffs of this convenience, however, was that food shopping became something less sensory than it had been before. When I try to remember how the Sainsbury’s of my childhood smelled, my mind is a blank, whereas I can still vividly recall the fresh grassy smell of the greengrocers where my mother used to go before, and the stale blood odour of the butcher where we bought our joint for the Sunday roast, and the heavenly scent of the warm bags of freshly ground coffee from the tiny coffee shop in the covered market.
In the early 2000s, two French sociologists studied how the sensory experience of food shopping started to change in Vietnam with the arrival of supermarkets. They found that in traditional markets, Vietnamese shoppers tended to pay great attention to the sensory qualities of different foods. They looked carefully for tomatoes that were pinky-red in colour with intact stalks, suggesting that the tomatoes had not travelled far. When buying meat, they smelled it and touched it with a finger to check for freshness. With the rapid expansion of supermarkets in Vietnam, this kind of close sensory observation became impossible. “In supermarkets, I buy without looking,” said one respondent. A similar process has taken place in Hong Kong, where researchers found that older shoppers had a much wider food-smell vocabulary than younger people. Older people had words for the particular odour of salted fish, of old tofu and of stale peanuts, whereas younger shoppers tended to speak only of food that was “fragrant” and food that was “stinky”.
All of this is part of a bigger revolution in eating over the past 50 to 70 years. It is one element in a process that Prof Barry Popkin has called the “nutrition transition”, which has happened all over the world as countries undergo economic development, and has transformed how and what people eat almost everywhere. There has been a shift from meals to snacks; from savoury to sweet; from local, homemade dishes to the same homogenised, ultra-processed foods made by multinational food companies.
This nutrition transition has seen a fall in the rates of global hunger, but it has also ushered in a vast rise in the prevalence of diet-related diseases, ranging from type-2 diabetes to heart disease, depression, asthma and some forms of cancer. In recent years, the concept of “malnutrition” has changed to include obesity as well as absolute hunger. In middle-income countries such as Brazil, rising numbers of people are both under- and over-nourished at the same time – suffering from a surfeit of calories but a dearth of the crucial micronutrients and protein our bodies need to stay healthy.
The question is whether it is possible to retain the prosperity of the nutrition transition while moving towards a less destructive economy of food. The problem cannot be fixed without radical government intervention. Healthy food needs to be made the affordable, available and normal option. This reform is all the more urgent in the wake of the war in Ukraine – the world’s fifth-largest wheat exporter – which will push the price of basic staples to unaffordable levels for many households. But while we wait for this structural reform to happen, what can we as individuals do to eat in happier and healthier ways?
One suggestion is that we start trusting our own senses more, and the slogans on food packets less. The food writer Michael Pollan once said: “If you’re concerned about your health, you should probably avoid food products that make health claims. Why? Because a health claim on a food product is a good indication that it’s not really food, and food is what you want to eat.”
When you really pay attention to what all five senses are telling you about food, you might automatically start to eat in a different and more pleasurable way. You might eat less, but appreciate what you are eating more. You reconnect with your own body and its relationship with food – at least, this has been my experience. I notice that when I am cooking, if I can breathe in all of the scents and sights of the cooking process, I feel nourished by them before I even sit down to eat.
The cookery writer Diana Henry has written frankly of how she released herself from a destructive cycle of yo-yo dieting, which she calls “the whole deprivation/rebellion, eating too little/overindulging rollercoaster”. In her 2014 book A Change of Appetite, Henry described how she was helped in this by adopting some of the principles of Japanese cuisine, which involve an intense appreciation of the sensory details in a meal.
Photograph: Popa Ioana/Alamy
Instead of asking how many calories a meal contains – calorie-counting is the very antithesis of sensory – a more fruitful and guilt-free approach to healthy eating is to notice and enjoy the balance of colours and textures and techniques in a meal while you are cooking and eating it. As Henry writes, “Eating is not just about sating appetite, but about appreciating, with all your senses, what is put before you.”
In some cases, making better use of the sense of smell can be a way to restore appetite when it has vanished. Many people living with dementia lose their interest in food and can become at risk of malnutrition. In 2013, Rodd, a British design firm, came up with a new product called Ode aimed at helping dementia sufferers to eat better. The device released waves of familiar food fragrances three times a day, in order to trigger positive food memories, and hence a desire to eat. The fragrances included comfort foods such as fruit pies, casseroles and curries. During a test phase, Rodd found that around 50% of the dementia sufferers who had been exposed to the food smells either stabilised their weight or gained weight [see footnote].
There are signs that modern societies could yet transition towards a new and more engaged culture of the senses. One factor helping to make this change could be the anti-plastics movement. On 1 January this year, the French government banned supermarkets and other shops from selling 30 types of fruits and vegetables – including cucumbers – in plastic wrapping. The motive for the reform was ecological rather than sensory: the French environment minister said that there must be limits on the “outrageous” proliferation of single-use plastic.
Some have defended items such as the shrink-wrapped cucumber on the grounds that the plastic actually helps reduce food waste. Stephen Dubner, author of Freakonomics, has cited evidence from cucumber growers that just 1.5g of plastic wrap can extend a cucumber’s life in the fridge by as much as 14 days. But at the same time, the plastic wrap makes it harder for the consumer to use his or her own senses to judge the freshness of the cucumber inside. An unintended side-effect of the plastics ban in France will be to bring supermarket shoppers closer to raw ingredients as they buy them. They will once again have the chance to see the dimples on a naked lemon before they buy it, or to smell the pungency of a leek that is not cloistered in plastic. If this reform could be repeated in other countries (Spain is to follow suit in 2023), it would be a significant step towards using our senses more actively when we eat.
A second reason to be hopeful is the rise in home cooking that happened during Covid lockdowns. Consumer research suggests that across Europe and beyond in 2020, there was a rise in purchases of ingredients for cooking from scratch, such as flour. People in Spain, Italy and Greece reported enjoying experimenting with new recipes during the pandemic. Anyone who cooks regularly will by definition use their senses in an active way. To cook is to become attuned to the scent of garlic sizzling in a pan, or the sound of a mushroom squeaking as it cooks. You learn to feel the smoothness of properly kneaded dough in your hand, or to notice the way that lentils or rice swells when it is perfectly cooked.
A third source of hope is provided by sensory food education. Learning to use all five senses more actively when eating is a teachable skill. In Britain, the new National Food Strategy authored by Henry Dimbleby in 2021 called for sensory food education to be a basic part of every young child’s education for nursery and reception classes. The evidence suggests that even a short course of sensory food education can help to broaden a child’s food tastes. A study from Finland found that sensory-based food education of pre-school children increased their willingness to eat a range of foods including fruits, vegetables and berries.
This effect was noticed even among children who were classified by their parents as “picky eaters”. Anecdotally, we have seen the same positive effects with TastEd. A teacher at the University of Cambridge primary school reported in autumn 2021 that a child in her class who had previously been phobic of new foods, and had been receiving specialist help from a dietitian for two years, had suddenly felt able to try three new fruits during a TastEd lesson. It seemed there was something about using her senses so actively that made the process of eating become something lighter and more pleasurable.
Perhaps the greatest cause for hope that a new culture of the senses may yet emerge is that although we live and eat in a world vastly different from our hunter-gatherer ancestors, we are still the same sensory beings underneath. If you want to start eating differently, the power is, to a large extent, in your own hands – with those marvellous opposable thumbs – as well as in your nose. (I am talking here about people who have enough to eat. Sensory joy and hunger do not go together.) Those of us who are still lucky enough to have a sense of smell should try to use it to the full while we can. Keep small pots of herbs in the kitchen or the garden if you have one. When feeling low, pick a mint leaf, rub it on your hand and inhale deeply.
Try to know your food with your ears, nose and hands as well as with your eyes. Smell it, touch it and look at it before you taste it. Explore the complex world of joy that is spice. Notice the many differences between fake emoji peaches and real peaches. Learn to recognise the equally huge differences between ultra-processed bread and real bread. Start to relish a range of tastes that go beyond sweetness. Appreciate the bitterness of grapefruit or the sourness of rhubarb. Next time you eat a particularly delicious pizza, try to notice why it was so pleasing: was it the dough, the sauce, the cheese or all three? Feel the ridges on a stick of celery or the soft embroidery on a leaf of kale. A human who eats without engaging their senses of smell, sound and touch is like someone who observes the world through a pane of frosted glass. For as long as you still can, squeeze the figs and smell the coffee. Come to your senses.
This footnote was added on 20 April 2022 to record that the Ode device is not currently available.
Adapted from Bee Wilson’s piece for an upcoming essay collection from Flevo Campus, a Dutch institute working to develop the urban food systems of the future