Historical and social science perspectives on food allergy

Abstract This article provides an overview of the insights social scientists, historians and other health humanities scholars have made to our understanding of food allergies. It shows how humanities and social science scholars have tended to address three pivotal issues related to food allergies: first, they have addressed the epidemiology of food allergies, including the apparent rise in the rate of food allergies and the emergence of theories that purport to explain why food allergies may be increasing. These include theories related to changes in food consumption and the hygiene hypothesis. Second, humanities and social science scholars have researched how risks related to food allergies have been constructed, understood, experienced and mitigated. Third, humanities and social science scholars have investigated the experiences of food allergy sufferers and those who care for them, providing valuable qualitative insights that can inform how we respond to food allergy and our understanding of the aetiology of food allergy. The article concludes with three recommendations. First, there should be a more interdisciplinary approach to food allergy research that involves social scientists and health humanities scholars. Second, humanities and social sciences scholars should be more willing to unpack and scrutinise the theories put forward to explain the aetiology of food allergies, rather than accepting them at face value. And finally, humanities and social sciences scholars can play a major role in ensuring that the experiences of patients and their carers are articulated and fed into debates about food allergy, including its causes and how to respond to it.


| ARE FOOD ALLERG IE S RIS ING AND, IF SO, WHY ?
Food allergies have become more widely recognised in many societies since the 1990s. More people appear to have food allergies today and there is greater awareness of them, thanks in part to public health campaigns. In many countries, most restaurants and cafes identify allergens, most supermarkets have 'free-from' sections and most schools and nurseries are 'nut-free' zones. Nevertheless, debates continue about how much of the perceived increases in food allergy are real or merely a reflection of increased awareness. 3,4 Historical research can provide a longer perspective.
The term 'allergy' was coined by Austrian paediatrician Clemens von Pirquet  in 1906 as 'any form of altered biological reactivity', a broad definition that precipitated arguments about how to define food allergy and distinguish it from food intolerance. 5 Until the 1930s, however, the term anaphylaxis, coined 4 years earlier by French Nobel laureate, Charles Richet , was the catchall for dysfunctional immune responses to insect stings, pollen and food. 6 The term anaphylaxis later took on its current definition of a severe, life-threatening allergic reaction ( Figure 1).
What about strange reactions to foods observed prior to the twentieth century? Historians get irked when today's diagnostic terms are carelessly applied to historical figures. 7 This is particularly problematic with psychiatric diagnoses, which vary enormously across time and place, 8 but quite speculative retrospective diagnosis of allergy also occurs. 9 With food allergies, however, we are assisted by the fact that the term idiosyncrasy was often used to describe unusual reactions to food. According to Jackson, the most common idiosyncrasies identified since the time of Hippocrates were related to food. (Table 1) 5 It is also possible to identify cases where physicians blame familiar symptoms, such as eczema, urticaria, migraine and asthma, on food. 2 This does not definitively mean that such cases were caused by food allergies. But it does indicate that for at least 2500 years, people have recognised that certain people react pathologically to foods that others find perfectly healthy. Indeed, historical records suggest the possibility that advice to the Chinese emperors Shen Nong and Huang Di over 4500 years ago included avoidance of specific foods during pregnancy, and to manage skin conditions which might have included eczema. 10 Figure 2). 11 Smith's research also indicates that there was medical and popular interest in food allergies prior to the rise in peanut allergies. 12 G R A P H I C A L A B S T R A C T Historians and social scientists scholars have addressed three issues related to food allergies: First, they have addressed epidemiology, including the apparent rise in the rate of food allergies and the theories proposed to explain these increases. Second, they have explored how risks related to food allergies have been constructed, understood, experienced and mitigated. Third, they have investigated the experiences of food allergy sufferers, providing qualitative insights that can deepen our understanding of food allergy.

Key messages
• Humanities and social science research can inform our understanding of food allergy.
• Scholars have concentrated on the epidemiology, risks posed by and experiences of food allergy.
• Humanities and social science scholars should play a larger role in food allergy research.
F I G U R E 1 Clemens von Pirquet and a patient. https://wellc omeco llect ion.org/works/ yd78ffbn. By the 1930s, food allergy textbooks and cookbooks were being published. One indication of a broader awareness of food allergy is demonstrated in a 1933 article about a walrus at a zoo believed to be suffering from food allergies. 13 After the Second World War, however, debates about the prevalence of food allergy emerge.
First, psychosomatic theories of allergy became prominent, prompting some allergists to suggest that symptoms, such as asthma or urticaria, were not caused by allergens, but were psychologically based. 14 By the 1960s and the publication of Rachel Carson's (1907Carson's ( -1964) Silent Spring (1962), allergists, such as Theron Randolph  and Ben Feingold (1899-1982 were beginning to blame processed foods and food additives for allergic symptoms. [15][16][17][18][19] There was also Selye's concept of stress, which situated allergy as a disease of adaptation. 20 The discovery of immunoglobulin E in 1966 by Japanese immunologists Teruko Ishizaka (1926-2019) and Kimishige Ishizaka (1925-2018) did little to resolve these disputes. 2  Social scientists have also explored the perceived rise in food allergies. In a 1997 paper, Cone and Martin attributed the rise of allergies and autoimmune disorders to changes in the production, transportation and consumption of food triggered by globalisation. 22 They speculated that, as people increasingly consumed highly processed and chemicalised food that was sourced far from where they lived, their immune systems were more likely to overreact to benign components in food, airborne particles, such as pollen, and even its own tissue. The essay built on Martin's pioneering anthropological research on immunology. 23,24 In terms of dietary change and the rise of peanut allergy, it is worth noting that peanuts and peanut products were consumed in great numbers long before the increase in peanut allergies during the late 1980s. A song about peanuts 'Eating Goober Peas' can be dated to the US Civil War era and peanut butter was invented during the 1890s. 25 Allergists and immunologists have provided indirect evidence that increased consumption of roasted peanuts in populations might underlie increases in peanut allergy. 26 However, research from Montreal, Canada during the 2000s also provided evidence that the rate of peanut allergy was plateauing in that city among young children, making questions about its epidemiology more complicated ( Figure 3). 27 Anthropologists have also tackled the hygiene hypothesis. Some have readily accepted the theory, even suggesting that adding more 'dirt' to our lives could reduce certain autoimmune diseases or exploring the hypothesis' social implications. 28 Clough, for instance, argues that girls in industrialised countries are expected to be cleaner than boys, meaning that they are exposed to fewer environmental microbes. 29 If the hygiene hypothesis is valid, she continues, this may explain higher rates of allergy, asthma, autoimmune disease and depression in women. Others have revealed the class dynamics of the hygiene hypothesis. Focussing on Canada, Minaker, Elliott and Clarke found that some allergists believed that people from wealthier backgrounds were more likely to have food allergies because they were thought to live in more hygienic environments (interestingly, the low-income people in their study blamed allergies on food additives, vaccinations and breastfeeding practices). 30 The corollary is that poorer people must live in dirtier environments. 31 Such classist assumptions may influence how clinicians think about the degree to which low-income allergic individuals will adhere to advice about avoiding allergens. This is despite the fact that poorer people often face more risks (real or imagined) from their allergies because they may have less access to epinephrine injectors, may not be able to afford hypoallergenic products and may have to access facilities, such as food banks, where there is a perceived risk of cross-contamination. 29 Another problem is conflicting evidence from the US about the relationship between socioeconomic status and food allergy. 32 Such a definition helps to explain how societies have dealt with food allergy. Food allergies have been associated with modernity and, while they themselves represent hazards, they have also bred anxieties not only about the direct threat they pose but also what they represent more generally. 5 To many they are a good example of what Rosenberg has called a 'disease of civilization'. 50 The mitigation of food allergy risks has taken a variety of forms, including the banning of potent allergens, especially peanuts, from public spaces, better labelling of ingredients and mandating the availability of epinephrine in schools. 51 47 This is particularly problematic in the case of peanuts and tree nuts, which are highly nutritious.
Social scientists also show that risk is understood subjectively by individuals. Peanut allergy, for example, has been described by DeSoucey and Waggoner as existing 'in the interstices of scientific facts, commercial interests, and shifting cultural tenets'. In turn, the risk posed by peanuts 'is a rich manifestation of disputes over the boundaries of responsibility for health and safety for self and others'. 53 Moreover, Cook has argued that allergic individuals do not perceive these risks on their own. 54 Instead, their perception is entangled in their response to particular physical and social environments, including the influence of other people. 55 An individual, for instance, might be more willing to poke around and sniff a takeaway meal consumed at home, than they would in a busy restaurant or at a dinner party. The way young people with food allergies perceive risk may be particularly fluid. Adolescents still rely on their parents to decide what is 'safe' for them in certain spaces, but they may simultaneously find themselves in situations where they have to determine the degree of risk themselves. Making this dynamic more complex are issues such as peer pressure and the fact that risktaking is a facet of life for most adolescents. 56 Nor is risk always constructed by allergic people straightforwardly. As Hu, Kerridge and Kemp have argued, 'rational descriptions of risk that exclude qualitative and emotion based evaluations will only partially explain the experience of risk, and the responsibility for risk'. 57 Gaivoronskaia and Hvinden's survey of people in Norway, for instance, found that those with food allergies were more likely to associate food with risk than those without food allergies. This finding may not be surprising, but the difference between the two groups (66% for the allergic group and 52% for the non-allergic group) was not as great as one might think. 58 Similarly, in a Netherlands study both allergic and non-allergic people were equally confused regarding the level of risk associated with specific precautionary labels present on foods. 59 Complicating the matter further are stories about particularly bizarre reactions to allergens, such as those apparently triggered by kissing another person or airborne allergens. 60,61 Such reactions may be breathtakingly rare and difficult to attribute, but-as with concerns about the exchange of bodily fluids during the early years of HIV/AIDS-they captivate us and the media, 62 and influence how individuals and societies calculate risk. 23,60 The ambiguities and uncertainties that Nairn has identified with immunotherapy for life-threatening food allergies also show how the perception of risk is contingent on numerous factors. 63,64 Immunotherapy for food allergy can be traced to 1908, just 2 years after von Pirquet coined the term allergy, but due to the risks involved it fell out of favour. 65 In recent decades, however, it has been hailed as a 'paradigm shift' in allergy treatment. [63][64][65] As Nairn has shown, however, variations in immunotherapy products and practices, and differing claims about what constitutes the 'best' ways to do immunotherapy-'standardised' FDA regulatory approved or in a | 907 SMITH 'real food' format-mean that allergic patients still have to contend with scientific and medical uncertainties. 63,66 This is not the least because external factors, such as stress, have historically been thought to exacerbate the severity of allergic responses, a factor under consideration again today. 67,68 In turn, scholars have also highlighted that psychosocial stress is another risk that people dealing with allergies face. The healthy development of children with food allergies is thought by some to be impeded by social isolation (e.g., from being excluded from activities, such as birthday parties) and anxieties about accidental exposure. 69 The food worries of both children and adults with food allergies have also been linked to increased levels of loneliness. 70  Indeed, some such scholars suffer from food allergies themselves or are the parents of sufferers. 60 The final section of the article, therefore, turns more in depth to approaches that attempt to capture the experiences of those coping with food allergies.  78 Mothers are also more likely to be tasked with liaising with schools and ensuring that a prevention plan is in place. 79 The rich, descriptive style employed by humanities and social science scholars can illustrate these experiences and emotions effectively. Cook's article on navigating food allergies in Japan, for instance, begins with a description of how the appearance of an ice cream van in a park on a hot summer day is a source of tension, not glee, for a 10-year-old with milk allergy. 80 Such a depiction helps the reader empathise more with those dealing with food allergies and stresses the role of fear (whether rational or not) in how people understand and experience food allergies.

This article was funded by a Wellcome Trust Post-Doctoral
Fellowship 088225/B/09/Z.

CO N FLI C T O F I NTE R E S T S TATE M E NT
The author has no conflicts of interest to declare.

DATA AVA I L A B I L I T Y S TAT E M E N T
This is a review article and is solely based on published material.