Allergic: Our Irritated Bodies in Changing World by Theresa MacPhail; Penguin Random House, $28.99
If you’re the parent of an elementary-school-age child, September probably comes with your yearly reminder that food allergies are A Thing. Maybe a flyer gets sent home that lists the “Big Nine”: milk, eggs, tree nuts, peanuts, fish, shellfish, wheat, soy, and sesame. Maybe you get a “Please do not pack” list, steering you away from using peanuts in your child’s lunches for the sake of their allergic classmates.
But if you’re the parent of that severely food-allergic child, the new school year means buying more epinephrine injectors, asking your kid to practice using one, begging them to consistently carry two, and filling out a Section 504 plan. You remind them that they can’t share snacks. You reiterate the places an allergen can hide, whether it’s almond flour in cookies or milk in liquid hand soap. You hope for the best and prepare for the worst, just as you do all 365 days a year. Every school lunch, birthday treat, holiday, team practice, field trip, and restaurant meal poses a threat to your child’s life. And foods aren’t the only allergy triggers—insects, animals, mold, dust, and plants all have the power to make us itch, wheeze, and swell.
In the prologue to Allergic: Our Irritated Bodies in Changing World, Theresa MacPhail reveals the loss of her 47-year-old father to a fatal bee sting reaction in 1996. Much has changed since then: ambulances and school clinics stock injectable epinephrine, and funding for allergy research has surged. Yet much is still unknown. MacPhail, who holds a PhD in medical anthropology, displays a persuasive combination of global health interest, bioscientific expertise, and journalistic chops as she unpacks allergy’s mysteries and nuances in this important book.
Allergic begins with a primer on immune pathways, noting that our understanding of them has periodically shifted or even reversed since Clemens von Pirquet’s coining of the term allergy back in 1906. Today, scientists define allergy in terms of histamine release, which weaponizes our immune systems against us and, in its direst incarnation, leads to anaphylaxis, a catastrophic reaction across multiple vital systems. Whereas the immune system operates differently in other conditions (like Celiac disease), we colloquially associate allergies with a range of chronic issues and autoimmune disorders, from lactose intolerance to Eosinophilic Esophagitis.
MacPhail opens the book with her own experience of being tested for allergies, first with a standard skin-prick trial and then a serological test, to show the journey we take toward allergy diagnosis today. A clear diagnosis might result in the advice to carry epinephrine or, in the case of a respiratory allergy, an inhaler. Inconclusive results might lead to over-the-counter antihistamine pills or a nasal spray to ease sniffles and discomfort.
Both skin and blood tests can yield false positives, yet the next step of a gold standard of a double-blind, placebo-controlled oral food challenge is considered too risky. Thus many households drastically reorganize to avoid an allergen without knowing for certain the severity of a child’s diagnosis—better overzealous caution that than a tragic loss. As MacPhail documents, caregiver exhaustion is real, as is the nagging question of whether an early decision in an infant’s diet (to expose or not to expose?) may have contributed to allergy formation.
MacPhail goes into rich detail about the medical field’s struggle to measure all types of allergy prevalence, track non-hospitalized reactions, and agree on what comprises an “allergy,” which can become a heated debate when discussing asthma or eczema. Viewed through the lens of science history, the story is gripping. Viewed through the lens of data analysis, it’s slightly maddening. Not surprising, then, that MacPhail’s thesis is holistic: “Our collective allergy symptoms … are trying to tell us something important about the overall health of our immune systems in the twenty-first century, about how we live our lives, about how overwhelmed our cells often are by our environment.” In other words, we’re receiving an SOS distress signal in the Morse code of hives. What specifically is causing it? What should—or can—we do differently?
There are a variety of proposed causes for allergies, ranging from individual genetics to family history to climate change. The barrier hypothesis pins allergies on leaky skin. The hygiene hypothesis looks at a disproportionate climb in allergy rates among urban dwellers, perhaps traceable to a lack of exposure to microorganisms in early childhood, i.e., playing in mud puddles on the farm. Germ theory instead blames allergy formation on increased exposure to external agents, in turn placing scrutiny on those living or working in environments deemed “unclean.” This is a particularly juicy approach, since it most clearly engages issues of economic opportunity and racial disparity, which—as MacPhail acknowledges—are relevant at all stages of thinking about allergy but too often absent from open discussion.
Key studies have affirmed certain correlations, and Allergic explores how pollen, particulates, and pollution affect lung function and may contribute to increasing allergies. The book avoids the peril of American myopia by looking at places such as Chandigarh, India, and including statistics from populations in China, Uganda, and other parts of the globe. And MacPhail notes that allergies aren’t just rising among humans, but also among our pets, underscoring the argument that home environment is a key factor. What she can’t do, through no fault of her own, is settle on a definitive explanation; that is a Gordian knot that eludes untying.
“At this point, you may be hankering for more information about how we might be able to change our diets to help balance our gut microbiomes, and thus our immune system,” MacPhail writes. “And while I understand this desire, I have to disappoint you yet again.” Local honey doesn’t cure, nor does genetically modified corn spell doom. That said, several of the experts MacPhail interviews are adamant about the effects of chemical exposure. “All the things we’re putting on our skin, or the things we’re putting on our babies’ butts, are probably not good for our barriers,” says Robert Schleimer, professor emeritus of medicine at Northwestern. Laundry detergent’s job, after all, is to break things down.
Once an allergy is established, the patient must devise their own formula for “treatment.” Approaches focus on avoidance, real-time rescue, experiments at desensitization, or some combination of the three. MacPhail offers compelling anecdotes such as one mother’s efforts to procure allergy-friendly access under the government-funded Women, Infants, and Children pantry program, resulting in her founding the Food Equality Initiative, and Congress’s investigation of Mylan’s scandalous EpiPen price-jacking.
The conversation around new treatments, such as biologic drugs for asthma or oral immunotherapy (OIT) to condition children against food reaction, is thorny. These are practices short on longitudinal studies and long on anecdotal evidence. MacPhail is frank about the potential side effects of monoclonal antibody treatments, including conjunctivitis or elevated eosinophil levels. She is also refreshingly open about the arguable value of OIT, which costs time, money, and potentially one’s mental health—children made to ingest foods that they have been taught are “unsafe” report extreme anxiety, hating the food’s taste, or both—yet seems like the panacea based on social media posts by the (financially secure, usually) parents of allergic children.
“Disability” isn’t in Allergic’s comprehensive index. But allergies can be productively framed within disability’s social model, in which institutions and cultures are charged with lessening barriers to inclusion (that’s why Section 504 plans exist). Air quality can be filtered. A restaurant meal can be made safer. De-emphasizing a “cure” fosters conversations that match real life, in real time. Just ask someone allergic to cats, who has a cat.
Readers looking for help may be frustrated to find that allergy diagnoses are not absolute, theories remain unprovable, and treatments yield inconsistent results. But MacPhail offers something more poignant and enduring than a handbook. Allergic is a brilliantly researched, provocative, and humane exploration of the ways bodies stay in dialogue with the world around us—even when they’re picking a fight.
