First Bite: How We Learn to Eat. Bee Wilson

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СКАЧАТЬ great pleasures since she was very young. Now it was tasteless. ‘Cinnamon drops, a childhood favourite, were bitter, horrible,’ she wrote in the New York Times. ‘Tamales were as bland as porridge. Bananas tasted like parsnips and smelled like nail polish remover.’ As for chocolate, it was ‘like dirt’.¹

      I got to know Marlena in 2002 on a press trip to Parma organized by the consortium of producers of Prosciutto di Parma. For three days we ate ribbons of pink salty ham at every meal and Marlena, with great Californian ebullience, talked about the foods she loved the most. These were long – very long – conversations. She spoke of artichokes and lemons; earthy dried mint and pungent truffles; bread and cheese; and how she would rather be in Italy than anywhere in the world. She ate with a dainty slowness, as if trying to extract the essence from each bite.

      After the accident, she could still perceive the heat of pungent spices such as mustard, Aleppo pepper or cinnamon, because her trigeminal nerve, the part of the body that tingles when you eat hot food, was not damaged. But without the flavour to offset it, the tingling sensation was offensive. Her beloved cinnamon felt abrasive. Meanwhile, she developed new cravings, for intensely sweet desserts and for fish. When I first knew Marlena, she was indifferent to desserts and hostile to fish. Now, suddenly, she had yearnings for smoked mackerel and anchovies. She also developed a very sweet tooth. A scientist working on flavour and the brain told her that this might be because she could no longer detect the qualities in fish and sweets that she had previously been disgusted by. They only seemed desirable because she couldn’t recognize the ways they had once repelled her.

      People sometimes speak of anosmia as ‘loss of taste’ but damage to the taste buds themselves is actually very rare. More than 90 per cent of cases of taste-related disorders involve a weakening or loss of the sense of smell. The taste buds in our mouths only supply a fraction of the complex pleasures that we enjoy as ‘flavour’. The rest is perceived via our noses, through something called retronasal olfaction. We smell coffee by breathing in – is any scent better than a warm bag of freshly ground beans? But we taste a cup of coffee by smelling it backwards, or retronasally. The hundreds of chemical compounds that go together to make up the flavour of a particular blend and roast of coffee travel to the back of our mouths and sneak backwards through the nasopharyngeal passage into the nasal cavity.² As we sip and swallow, we are not conscious that the splendid flavours – the nuttiness of the roast, the notes of cherry and peach – are created in the nose, not the mouth. This spectrum of retronasal joy is lost to anosmia sufferers. All they have left are the harsh and basic tongue-notes of sweet, sour, bitter and salty. Like Abi Millard enjoying a salty gammon steak, anosmia sufferers often seek out extremely salty or sweet foods to compensate for the loss of flavour.

      Anosmia is a surprisingly common problem – as many as 2 million people in the US have some form of smell or taste disorder.³ It is not a trivial disability. The ability to pick out the jasmine aroma in a cup of espresso or to spot the difference between grapefruit and pomelo might seem of little importance to anyone except for food writers. But medicine and neuroscience are now starting to recognize that anosmia can be an extremely traumatic condition, and not just because of the danger in emergencies of not detecting the smell of smoke or gas. Sufferers often end up depressed and malnourished. Without flavour, the motivation to eat is lost. When nothing can be smelled, there is a yearning for familiar tastes that can never be satisfied. Christmas goes by without the background aroma of turkey or spice; summers are no longer marked by the perfume of strawberries and cut grass. Sufferers often describe it as a deep loss. Duncan Boak, the founder of Fifth Sense, who became anosmic after a head injury, said that he feels as if he is looking at life through a pane of glass.⁴

      Part of what is missing for the anosmia sufferer is the safe place of childhood, which the rest of us can return to whenever we eat the foods we have always loved. A couple of years on from the accident, Marlena Spieler found that glimmers of her former responsiveness to flavour were returning. Depending on the level of damage to the brain, some anosmia sufferers do recover. Marlena slowly trained herself to love chocolate again, starting with the blandest milk chocolate and working onto 70 per cent cocoa solid dark chocolate. Occasionally, her morning coffee gave her pleasure rather than just blankness. We met for lunch at an Italian restaurant and she seemed well, exclaiming over the blood orange slices in our cocktails and nibbling on a deep-fried sage leaf. But even as her flavour perception was improving, she continued to feel unsettled, she said. It wasn’t just that food tasted bad. It was that, she told me, she no longer felt quite ‘like Marlena’. As she explained to the BBC Radio 4 Food Programme, our sense of taste is something that anchors us to the person we have always known ourselves to be: ‘Your world has a certain taste. Your mother makes something a certain way. You’re used to certain flavours in your life and if you take that away, you start saying who am I?’⁵

      Memory is the single most powerful driving force in how we learn to eat; it shapes all our yearnings. Sometimes the memories are very short-term ones – for instance, whether or not we’ve just eaten. In one study, when a profoundly amnesiac patient was offered another meal only minutes after he had completed the first, he willingly took it.⁶ Minutes after that one, he ate a third meal. Only when a fourth meal was offered did he refuse, telling the experimenters that his ‘stomach was a little tight’.⁷ This suggests that having a conscious memory of our last meal matters as much as hunger in determining how much we eat.

      For most of us, though, the food memories that really matter go much further back. You may not be able to remember what you had for lunch last Tuesday, but I bet you can recall the habitual meals of childhood; the breakfast you were given for a weekend treat and the way bread tasted in your house. These are the memories that still have emotional force years or even decades later.

      Such memories, conscious or unconscious, are what drive us to seek out the old habitual foods – particularly packaged foods – even if, judged objectively, they do not really taste nice or do our bodies any good. There have been experiments done with rats and mice where the animals are given dopamine blockers, drugs that interfere with the part of the brain that governs reward. These drugs take away much of the chemical reward of eating food. Yet the dopamine blockers do not extinguish the rodents’ food-seeking behaviour, at least not straight away. At first, the animals continue to press the lever (or run through the alleyway, or whatever the task might be) and eat the pellets, even though the dopamine blocker means that the food no longer offers the same gratification.⁸ Next, they carry on pressing the lever to earn the pellets, but do not eat them. Finally they stop pressing the lever, indicating that at last their desire for the pellets has gone. The interesting thing is that it takes so long for the desire to fade. As the neuroscientist Roy A. Wise has observed, it is only when ‘the memory of the reward is degraded through experience that the desire is lost’.⁹ The craving for the pellets is more a function of memory than of how they taste. Memory propels human food urges in much the same way. As we traverse the supermarket aisles in a trance-like state, we are like rats in an alleyway, steered to this or that food by memories of rewards long gone.

      One of the reasons that we do not usually think of our tastes as learned is that most of the learning tends to happen in the very early years of life; and then it stops. For those of us who believe in personal development, it is depressing to learn that a person’s food ‘likes’ aged two generally predict their tastes at twenty. In 2005 researchers in Turkey interviewed nearly 700 undergraduate students and their mothers.¹⁰ The mothers were asked about their children’s eating habits when they were two and the students were asked about how they ate now. There was a remarkable continuity between then and now. The students who were ‘picky eaters’ as children still described themselves as picky eaters. The ones whose mothers recalled that they always ate too much still did so. And the three people in the study who ‘never’ ate vegetables as children still had no vegetables in their diet. So much for putting aside childish things.

      When we talk of memory and food, we generally assume that nostalgia is a phenomenon that occurs late in life – like Proust being transported to СКАЧАТЬ