In August 2009, fans attending an AC/DC concert at Commonwealth Stadium in Edmonton, Alberta were prohibited from bringing peanuts into the stadium. As Smith reveals, some fans were angered by the ban – either refusing to believe that peanut allergies could actually be this severe, or asserting that allergy sufferers needed to assume responsibility for their own health by carrying an epi-pen. In response, allergy sufferers highlighted the life-threatening nature of their condition. Smith argues that the relatively sudden emergence of anaphylactic peanut allergy has transformed our understanding of food allergies: while the possibility existed of a much broader understanding of the impact of food allergens on our overall health in the 1960s and 1970s, the emergence of anaphylactic peanut allergy gave orthodox allergists the upper hand and led us, as a society, to understand food allergy in narrower ways. While the peanut controversy lies at the heart of this well-written and engaging book, Smith also provides a broad and thoughtful history of food allergy that takes into account medical debates over what constituted food allergy, parent activism and the relationship between food, allergy and our environment. Along the way, Smith provides some intriguing comparisons between the history of allergy medicine and the history of psychiatry, arguing that both fields have been too driven by ideology and that a more pluralistic approach would be more useful for both historians and for patients.

Smith argues that prior to the twentieth century, the concept of food allergy did not exist, but physicians believed that idiosyncratic reactions to food could cause a host of conditions including: asthma, eczema and headaches. Smith takes the view that it is likely that people were allergic to foods, but because other food-related conditions such as malnutrition and food-borne pathogens were so much more severe, these idiosyncratic reactions to food were probably deemed of little consequence except to the wealthy. The field of allergy emerged in the early years of the twentieth century and Smith focuses on three researchers to demonstrate the diversity in the field. The term ‘allergy’ was first coined by the Austrian Clemens von Pirquet in 1906 to refer to ‘any form of altered biological reactivity’. At roughly the same time, the French physiologist Charles Richet described anaphylaxis in dogs, winning a Nobel Prize for this work in 1913. Finally, the Irish physician Francis Hare, published The Food Factor in Disease in 1905. He argued that a variety of medical conditions including migraines, asthma, skin conditions and mental illness were caused by diet. Like the researchers that would follow in their footsteps, these researchers represented a range of views: some allergists would regard allergy as a relatively rare condition with severe symptoms, while others believed that food allergies caused a wide range of conditions and ailments. Smith points out that many of the more liberal theorists of the ubiquity of food allergy suffered from allergies themselves: one of the most enthusiastic proponents of food allergies, Arthur Coca, rarely left his house in his older years, fearful of encountering one of the many allergens that he reacted to. When he dared to venture out, he packed all of his own meals.

An important point of division in the field had to do with testing for allergies. Skin tests quickly became the primary means by which allergists identified allergens. But skin tests did not work very well for food allergies and could also be dangerous. Food allergists preferred to test for food allergies through elimination diets. Orthodox allergists regarded this as less ‘scientific’ than skin testing, but as Smith points out, skin testing was also tied into the development of desensitisation treatments, which involved the development and sale of pharmaceutical products.

In general, food allergists, in contrast to orthodox allergists, believed that a far wider range of conditions could be linked to food allergies, including problematic childhood behaviour, while orthodox allergists often believed that their patients’ symptoms were the result of psychological disorders. Smith briefly reviews the career of Benjamin Feingold (which he has discussed in much greater detail elsewhere) to argue that Feingold had been a fairly mainstream allergist until he became convinced that food additives were leading to an epidemic of hyperactivity among children. At the same time, other allergists were becoming alarmed about the impact of food additives, pesticides and pollutants on their allergic patients. Theron Randolph became a leading advocate for the view that human health was being endangered by the new chemical environment and in 1962 he published Human Ecology and Susceptibility to the Chemical Environment that dealt with sensitivities to chemicals in water, air and processed foods. Three years later, he formed the Society for Clinical Ecology. New concerns about hyperactivity and chemical sensitivities helped to give birth to allergy-testing laboratories and ‘physicians promising cure-alls’ that Smith criticises as little more than ‘snake-oil salesmen’ but he also condemns the orthodox allergy community for lumping together ‘established clinicians’ like Randolph and Feingold with ‘cranks and quacks’. (p. 149)

Smith argues that the field of allergy changed fundamentally in the 1990s when anaphylactic reactions to peanuts emerged as a major issue. Activist groups formed by the parents of severely allergic children played a vital role in raising the profile of food allergy, but in doing so, they helped to realign the field along more conservative lines. The Food Allergy network for example, focused on some of the most severe allergies including milk, egg, peanut, soya, fish, shellfish, wheat and tree nuts. This decision helped win them support from orthodox allergists. But it meant that clinical ecologists were marginalised.

Throughout the book, Smith stresses that a more pluralistic understanding of allergy could have led to better results for both food allergy sufferers and for the science of allergy. In a discussion of the debate over the psychosomatic origins of allergy symptoms, for example, he points out that many researchers today stress that allergies themselves may lead to psychological distress and suggests that this conclusion might have been reached earlier had allergists been more willing to consider other points of view. Likewise, in the conclusion, he urges allergists to pay more attention to the causes of the increase in allergies (which he believes are likely multiple) and less to simply providing treatment.