The Unpoetic Calorie

What​ is it about the body that resists plain description? When we discuss our bodies, we evoke other things: the body as machine, possibly malfunctioning; the body as computer, infinitely programmable. The body as input-output system, or stardust. The electrical wires of the nerves, the mainframe of the brain. We start young: my train-obsessed three-year-old thinks of his digestive tract as a track, as if it were a series of signalling booths and stations. Why not? Is this metaphor any less apt than memory as data storage, or the immune system as besieged city? Something compels us to map flesh to image. The history of the body is partly a history of metaphor, of poetry.

As in poetry, no metaphor is ever really superseded by another. One way of writing the history of the body would be to work backwards through the likenesses: before the body as computer there was the body as chemical system, and before that there was the body as machine and the body as fluids, but this neatens a chronologically messy story. All these images survive in our ways of thinking about the body, even as our own language tends increasingly towards the technological. But the deep history of the body is still buried in our conversation. No one who uses the phrase ‘good-humoured’ is now referring to a harmonious state of inner juices, though that is the sedimented meaning.

The brain as computer: is this the best we can do? The computer is so obvious; we spend so much of our days touching it, melding our minds with it. The premodern imagination was more ambitious. From ancient Greece to the Enlightenment, men and women looked into the fire or up at the sky to discover what their flesh was like. Four elements made up the visible world, each with its own qualities: earth (cold and dry), fire (warm and dry), water (cold and moist), air (warm and moist). The four seasons had distinct associations: spring, for instance, was warm and moist, with its gentle breezes. The body was composed of four humours, fluids that nourished organs and replaced spent flesh; each was connected with one of the four elements. The humours were like something beyond themselves: like winter, like delved earth, like the rotation of the stars in the heavens.

What kind of person were you? Clues to your particular composition of humours were abundant. Did you tend to have pleasant dreams, of dancing or laughing or embracing beautiful women? Did you have red hair, or at least pink cheeks? Did you look on the bright side? Then you were probably sanguinary, dominated by hot and fortifying blood. If you had dark hair and a temper and slept fitfully, dreaming of shining objects, fires or arguments, you were likely to be choleric, yellow bile flooding your body. Philosophers and scholars, whose minds ‘must of Necessity be disjoyn’d from the Senses’, were governed by melancholy, cold and dry black bile; they might also suffer from depression and anxiety, and were advised to forego venison (deer are shy, and would make you more withdrawn). If you were a little sluggish, dull, pale and reserved, if you dreamed of icy rivers and snow, you were phlegmatic – or perhaps just a woman, running cold and moist.

Humoural theory was very old, first theorised in the Hippocratic corpus of 430-330 BCE, later codified and developed by Galen, and it was astonishingly durable, only seriously challenged by the experimental natural philosophers of the late 17th century. It was also capacious and mutable. You might be predominately choleric, but prone to a touch of melancholy now and then; or sluggish and phlegmatic, but only after lunch. Diet mattered because the humours were thought to be ‘concocted’ from the food you consumed. Premodern medicine was preoccupied with the relation between the ‘natural’ state of the body – your temperament, anatomy, the shape of your organs – and the ‘non-naturals,’ the variables under your own control. Along with food, the non-naturals included environment, rest and movement, sleep and waking, excretions and the passions. This medical culture was called dietetics. Premodern physicians could determine your humoural balance by studying the way your blood clotted or by examining a flask of your urine. But in its vernacular guise, dietetics wasn’t all that mysterious. The humoural system put your insides on the outside, made character and passions knowable from skin, face, hair, manner of speech.

Most important, dietetics allowed – required – you to know yourself. Where to live, how to sleep, what kind of exercise to take, when to have sex, how to control your emotions, what to eat and drink: all were determined by your fluid temperament. Dietetic knowledge was a matter of self-diagnosis, informed by your own appetites and routines. The governing rationale was analogy, a kind of thinking that made everyone both physician and poet. A popular manual declared that ‘Every sort of Food hath its operation in the Body, and on the Spirits by way of Simile.’ Early modern medical texts listed the properties of foods so that you could plan your meal to suit your complexion. Peaches were cold and moist, dried beans cold and dry, garlic very hot and very dry. Depending on your state of health and habits, you might want to match your food to your temperament, or you might wish to correct it by eating opposites.

This ancient mode of thinking about the body attracts me. It is so much more beautiful than our cold psychological categories, and so unfamiliar in its insistence that we are not separable from the world. ‘We our selves have had ourselves upon our trenchers,’ as one 17th-century medical advice book put it: a strange, almost cannibalistic idea, that we find ourselves on our own dinner tables. And so our bodies could be remade. The 16th-century French physician Ambroise Paré wrote that ‘If Custom (as they say) be another nature, the Physician must have great care of it … For this sometimes by little and little, and insensibly, changes our natural temperament, and in stead thereof gives us a borrowed temper.’

Concordances were everywhere. When a cow was slaughtered its brutish nature became concentrated in its spattered blood and in the mist of its last breaths. Hence butchers were known to be fierce and cruel, their bodies penetrated by the inhuman qualities of the beast whose blood and breath clung to their skin. A plant with a leaf or a seed pod in the shape of the human stomach should be administered to someone with stomach-ache. This was the doctrine of signatures, the idea that God signed nature so that we would know what to do with it. Quod sapit nutrit: what tastes good is good for you. Such was the ‘infinitely wise Contrivance of Nature’, according to one 18th-century physician. And what was good for the body was good for the soul, for ‘there is great concord betwixt the bodies qualities, and the soules affections.’ We incorporate matter, and it reincarnates us.

Steven Shapin’s​ Eating and Being is a history of dietetics, and of the ideas about eating that succeeded it, all the way up to the unpoetic calorie. Shapin is an eminent historian of science whose work has taught us much about the social worlds in which scientific knowledge was created, and he argues here that thinking about food is also a way of thinking about some of the most fundamental categories of human physiology, personality and morality. Dinner is never just dinner. The history of science has often valorised moments of revolutionary change – discoveries, inventions – but dietetics presents a challenge to the paradigm of the paradigm shift. It is a medical culture characterised more by longevity and conservatism than originality. Shapin traces the slow and uneven transformations in the ways people imagined their bodies to work, how food made flesh; in his telling, this isn’t a story of radical change but of ‘layered pasts, a surface through which supposedly past sentiments intermittently intrude, one in which some elements of the past were never completely submerged’.

The first serious critiques of the humoural system were mounted by natural philosophers in the 17th and 18th centuries. These men saw the body not as an economy of fluids but as a machine: Robert Boyle advised that the physician should ‘look on his Patients Body, as an Engine, that is out of Order’; Nicholas Robinson, that the human body was a machine with a system of ‘Springs, Wheels and Pullies’ that needed to be balanced. The physician George Cheyne combined the old humoural system and the new mechanical one to charming effect: the body was ‘Branching and Winding Canals, fill’d with Liquors of different Natures’, the digestive tract ‘as it were, a Common Sewer’. The proper business of medicine was not to manage the concoction of fluids, but to keep the machine of the body working: the springs springy, the canals flowing, the sewers draining, the engine of the heart pumping.

The natural philosophers severed the link between sensory experience and knowledge that underlay the humoural system. Take a peach. Its sweetness, coldness and moistness were no longer intrinsic qualities of the fruit, as in the humoural system. In Cartesian philosophy, a peach’s sweetness came from micromechanical particles, invisible to the eye; they were small, possibly triangular, and moved rapidly, tickling the tongue and giving the sensory impression of sweetness. The analogies between body and world broke down. Micromechanical particles were the province of experts, because the qualities of flesh and food were now a matter of the intellect: of philosophy, perhaps, rather than poetry. As Locke had it, ‘There is nothing like our Ideas [of our bodies], existing in the Bodies themselves.’

At least, that was the theory. Sniffling in bed with a cold, even micromechanical philosophers gave up on particles for something cosier; when Pascal was unwell, Descartes suggested soup. The fashionable new physicians of 18th-century London, Edinburgh and Paris mostly encouraged ways of living and eating that would have been familiar to their grandmothers (and mine, for that matter): moderation in all things; eat lots of vegetables; know your own body and its customs; don’t think too hard, especially after supper. As late as the 1830s, medical manuals were referring to the ‘four principal constitutions’: the four humours, under new names. But by then the scientific discipline of chemistry had come to dominate the study of food and the body. Food didn’t have qualities anymore, not even micromechanical ones, but chemical components: elements and compounds. This was the language of the laboratory rather than the kitchen. The ideals of balance and moderation survived the humoural system but were reconfigured. Your ailing body might now be diagnosed as too acidic, and you might be advised to eat alkaline foods.

Some of this was common sense. Fish, ‘being highly alkalescent, wants to be qualified by Salt and Vinegar’, John Arbuthnot pronounced, but anybody could see this was fish and chips spun as science. In other ways, things were becoming much more complicated. In the 1830s and 1840s, chemists began to tabulate the elements in food. Nitrogen, phosphorus, sulphur and iron were not things you could taste or touch or see. Similes and analogies, philosophy and mechanics, were submerged under the new and highly technical vocabulary of nutrition science. In The Physiology of Taste (1825), Jean Anthelme Brillat-Savarin – ‘that great ghost born in Belley who ate like a fat parson,’ in M.F.K. Fisher’s description – wrote about gastronomy as a science. His famous aphorism, ‘tell me what you eat: I will tell you what you are,’ wasn’t referring to humoural fluids or micromechanical particles, but chemical compounds.

Soup survived these transformations. The chemist Justus von Liebig, who had theorised the nutritional power of protein to remake spent muscle, became obsessed with extracting the most nutritious elements of beef and turning them into broth. He was on the hunt for osmazome, a mysterious compound that made meat savoury, nutritious and, well, meaty. He came up with a recipe, worked with a railway engineer to industrialise the production of beef extract, and founded Liebig’s Extract of Meat Company, which eventually became a massively profitable multinational after trademarking the Oxo cube. Mrs Beeton called Liebig the ‘highest authority on all matters concerned with the chemistry of food’, but Eliza Acton, in her popular Modern Cookery, for Private Families (first published in 1845), didn’t cut out the housewife altogether. ‘The stock-pot of the French artisan supplies his principal nourishment; and it is thus managed by his wife, who, without the slightest knowledge of chemistry, conducts the process in a truly scientific manner.’

At the end of the 19th century, Wilbur Olin Atwater applied laws of thermodynamics to the human body. He found that he could use the calorie – a unit of energy – to translate food into numbers. Nutrition science became concerned with measuring how much fuel different bodies needed for different kinds of work, in order to maximise the productivity of the labouring classes. With his fancy new respiration calorimeter, Atwater calculated the caloric expenditure of men cycling and thinking, and of women knitting and doing the washing up. A seamstress in London needed 1820 calories a day. A cabinetmaker in Leipzig, 2757. A ‘Well-fed Blacksmith’ in England, nearly 5000. Nutrition scientists applied their minds to the scourge of ‘irrational cooking’: housewives overcooking the meat, wasting money on steak when they could be buying beans, supplying their husbands with liquor but not protein. ‘Of course, the good wife and mother does not understand about protein and potential energy and the connection between the nutritive value of food and the price she pays for it,’ Atwater wrote, ‘and doubtless she never will.’ Despite Atwater’s pessimism about the housewife’s intellect, she was at the frontier of nutritional knowledge. The US Department of Agriculture sent women pamphlets on practical cooking and information about macronutrients; agricultural colleges implemented short courses in domestic science for women.

By the mid-20th century, the language of nutrition science – of calories, protein, metabolism – was, in Shapin’s assessment, ‘incompletely but substantially’ part of the way most people thought about nourishing their bodies. It was certainly the dominant way of imagining the body during my childhood. We studied the USDA food pyramid at school; in our dining room cupboard at home there was a little book of calorie counts, next to the little book that told you how to get various stains out of tablecloths. But as Shapin points out, nutrition science did not systematically supersede what came before. My grandmother gave us chicken soup when we were ill, not for its macronutrients but for hazier reasons probably not all that different from Descartes’s when he tended to Pascal. Shapin is scrupulously non-partisan about this long history. He doesn’t see the development of modern nutrition science as a story of unalloyed progress; nor does he suggest that the premodern past contains plenty of folksy wisdom we ought to recover. He argues instead that we should appreciate ‘continuity through change’, the stratified images and theories of the body that still inform our thinking and haunt our language.

Shapin does claim that with the decline of dietetics, the concept of ‘what was good for you’ was severed from ‘what was good’. In premodern Europe, he writes, ‘how to eat was a substantial answer to questions about how to be.’ Eating too much, for example, was a sure route to other states of dissolution: ‘Gluttony is the forechamber of lust,’ one 17th-century writer observed, ‘and lust is the inner roome of gluttony.’ The medical was frequently moral, the moral medical. With nutrition science, Shapin says, ‘the consumption of food is an instrumental act – having to do with maintaining health and function – and moral management is a matter wholly different from feeding the body.’ What you eat can be an exercise of choice and willpower, however, and might express the kind of person you are: one who cares about climate change, or animal rights, or supporting local businesses. There is still a morality to food.

Few physicians would now counsel their patients about the connections between diet and sexuality, or diet and virtue. ‘If you want to know what is moral,’ Shapin writes, you might go to ‘your priest, imam, rabbi or professional ethicist’. But I grew up believing that eating and virtue were much the same thing. I read celebrity magazines like scripture – they were my adolescent moral compass – and I think I could still tell you the daily calorie intake of most early 2000s popstars. The nutritional information on the back of the box has never been a neutral and scientific guide to health, or not only that. It tells a more inchoate story of hunger and shame and can set off an inner alarm: you shouldn’t eat this, because Britney Spears ate just a grilled skinless chicken breast for lunch in 2001 (180 calories). If being thin is its own moral reward, then eating becomes a problem of moral management; the body a proof of character, a manifestation of that greatest of female virtues.

Still, not even Atwater’s calorie could kill off the physical pleasure of eating. Through the decades of austere nutrition advice there was Julia Child, swirling her pan of butter. The historian Alan Bray once argued that the premodern past was distinctive for its blurring of satisfactions, the insistence that it all feels good: sex, eating, getting drunk, dressing up, dancing, fighting, going to bed. The metaphors might stack one on top of another but underneath them is the simple delight of licking your lips and tasting butter, or wine, or smoke. That the sensory pleasures of eating can survive all that history seems almost a miracle. But Brillat-Savarin had already put this much better, in the Physiology of Taste: ‘The pleasures of the table belong to all times and all ages, to every country and every day; they go hand in hand with all our other pleasures, outlast them, and remain to console us for their loss.’