Growing up in Alberta during the 1980s, there were two things I could count on: there would be snow on the ground by Halloween and my school lunchbox would contain a peanut butter sandwich. Today, due to climate change, Albertans can’t even count on a white Christmas. As for peanut butter sandwiches, they are unlikely to be found anywhere near a school, whether in Alberta or elsewhere. Certainly, my children have never been permitted to bring peanut products to school in Scotland. The reason for this is fear of peanut allergies. Can we explain the recent rise in peanut (and other) allergies? The answer to this question, frustratingly, is no.

As Theresa MacPhail explains in Allergic, peanuts are just one of many allergens that frustrate clinicians and researchers, while making the lives of billions (yes, billions) of people miserable. From the ubiquitous hay fever and asthma to the rarer eosinophilic esophagitis (an inflammation of the oesophagus caused by food allergies) and meat allergies caused by lone star tick bites, allergic reactions are increasing and becoming deadlier. Although allergy statistics can be unreliable, the World Health Organization estimates that nearly half of all schoolchildren are sensitive to at least one allergen. MacPhail, a medical anthropologist, set out to discover why, and what can be done. Her book ultimately contains more questions than answers.

Allergic is divided into three sections: ‘Diagnosis’, ‘Theories’ and ‘Treatments’. In ‘Diagnosis’ – and throughout – MacPhail endeavours to ensure that her readers understand how to define allergies precisely. This may be well intentioned, but it goes against the grain of one of the key themes in the