Illustrations by Julia Dufosse for Elemental

Food Allergies Remain a Mystery. Why?

The rise in food allergies has been weighing on the health system for a couple decades now — with little understanding of where it came from and where it’s headed

During a grocery run long before the Covid-19 pandemic, Michael Pistiner, MD, a second-year pediatric allergy fellow at Children’s Hospital Boston, was standing in a Boston Whole Foods aisle basking in the glow of how darn cute his son Scott was. His three-and-a-half-year-old had just tasted a chocolate bar with walnuts for the first time and said, “That’s delicious!” It was such a big word. A nice moment for father and son.

As an allergist in training, Pistiner knew he was doing everything right, exposing his totally healthy child to a walnut at the American Academy of Pediatrics-recommended age. But then things took a turn. Scott started pulling at his tongue and saying that he couldn’t get the taste out. Pistiner said to his wife that their son could be having an allergic reaction even though it seemed absurd.

“Shut up,” his wife said, joking that his professional life was going to his head. Pistiner was dissuaded. He rationalized that it wasn’t serious. But by the time Scott began puking in the fish department, Pistiner knew his initial diagnosis was correct. Scott was rushed to the hospital where, indeed, he was having an anaphylactic reaction.

The Pistiner family’s experience has become common in the United States. What follows for many after a child’s severe food allergy attack is a lifetime of adaptation and compulsory readiness. According to a 2018 clinical study published in Pediatrics, 7.6% of American children have food allergies. That’s close to 6 million kids. Or, one in 13 children. Two in every classroom.

Everyone is now focused on the Covid-19 health crisis, as they should be, but there’s another affliction — the rise in food allergies — that’s been weighing on the health system for a couple of decades now with little understanding of where it came from and where it’s headed.

A food allergy occurs when a person’s immune system mistakes a nonthreatening protein as being dangerous. As it turns out, the proteins within today’s most prominent allergens (milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, and soybeans) do not easily break down when cooked or exposed to stomach acid. They are therefore more likely to cause a reaction.

Food allergies have been among us for some time. There are historical texts from ancient China, Egypt, and Greece that refer to adverse reactions to food. Roman poet Lucretius’ famous line, “what is food to one man is bitter poison to others,” has been attributed to an allergic reaction diagnosis, even if it does sound like he was just being… poetic. It wasn’t until the 19th century that modern medicine began to understand allergies. England’s Charles Harrison Blackley identified pollen as being the cause of hay fever and in 1906 Clemens von Pirquet, an Austrian doctor, coined the term “allergy.”

By 1967, scientists pinpointed immunoglobulin E (IgE) as the antibody responsible for most such reactions. When an antigen, or foreign substance, enters an allergy-prone person, the body releases IgE, which sets off a chemical reaction that manifests itself as rash, swelling, shortness of breath, stomach irritation, and, in worst cases, anaphylaxis, which is a whole-body reaction that can involve a severe drop in blood pressure and constriction of airways that could lead to asphyxiation. Anaphylaxis can be reversed by a shot of adrenaline, or epinephrine, which raises the blood pressure and opens the airways in the lungs. In 1987, the FDA approved the EpiPen, an auto-injector of epinephrine, which allows anyone with a prescription to administer the medication to themself in case of an emergency.

Lucretius’ famous line, “what is food to one man is bitter poison to others,” has been attributed to an allergic reaction diagnosis, even if it does sound like he was just being… poetic.

In the early 1990s, the prevalence of allergies began to rise. The increase continues today — there’s been no flattening of the so-called curve: 32 million Americans now have some form of allergy. According to the U.S. Centers for Disease Control and Prevention (CDC), there was a 50% increase in food allergies among children from 1997 to 2011. What’s more, peanut allergies increased 21% from 2010 to 2017, so that close to 2.5% of children are now affected. Annually, 200,000 people require emergency medical care for an allergic reaction to food.

But what the numbers don’t tell is the experience that each of those individuals and families afflicted with food allergies goes through; the initial discovery of a food allergy, the reaction, the hopefully non-life-threatening result, and then the everyday life lived in a defensive war.

For those who aren’t close to someone with a serious allergy, it may seem like a national psychosomatic trend. And that’s why this is an invisible war, unlike the one being waged against Covid-19. Allergies are difficult to see. Hard to understand or rally around. The combatants are caregivers and their children. The battleground is in kitchens and schools and on planes and playdates (in the before times). It’s happening every day. For many, it feels endless.

I am one of those parents. My 10-year-old daughter was diagnosed with allergies to egg and peanut after she threw up when she ate some egg when she was a one-year-old. My wife and I were incredulous. Our doctor told us to go to an allergist. We went to world-renowned pediatric allergist Scott Sicherer, MD, at the Jaffe Food Allergy Institute at Mount Sinai Hospital. We were told our daughter had an egg allergy that she might grow out of, and a peanut allergy that is probably permanent. No cure. No treatment. No definitive cause. All we could do is avoid eggs and peanuts, arm ourselves with epinephrine pens in case the worst happens, and hope for the best.

“This is an invisible war… The battleground is in kitchens and schools and on planes and playdates (in the before times).”

Someone said to me at the time that our daughter’s allergy was “a game-changer,” suggesting our lives were never going to be the same. I didn’t like that. It’s more like you play the same game, but with more padding. Having been fortunate enough not to ever have experienced anaphylactic shock, my daughter has experienced her allergies as an inconvenience but nowhere near like having a life-threatening illness. There are actually very few mortalities from food allergies each year; the FDA estimates that annually there are 150 deaths in all age groups. But it’s not nothing.

Coping with a child’s condition that limits what they can eat — with a very steep downside if anything were to go wrong — puts you in a murky world, not exactly fighting for their lives but certainly more than advocating for a quality of life issue like adequate recess time. It may be a first-world problem (literally; developing nations haven’t had the same increase in allergies) but it’s one that many first-world parents now face. Having my daughter at home during the pandemic has provided more control. But as the much-needed vaccines roll out and the U.S. can begin to imagine a return to normalcy, I feel nervous.

Though food allergies have been increasing for decades, the source of the increase remains a head-scratching mystery. “The hardest question is, ‘Why?’ Nobody knows,” says Ruchi Gupta, MD, a professor of pediatrics at Northwestern Medicine and the Ann and Robert H. Lurie Children’s Hospital of Chicago.

Gupta agrees with the consensus belief shared by the other allergists I spoke with, including Pistiner, who is now Director of Food Allergy Advocacy, Education and Prevention, Food Allergy Center at Massachusetts General Hospital, and Shahzad Mustafa, MD, the lead physician at Rochester Regional Health hospital’s Allergy, Immunology, & Rheumatology department, that the increase is “multi-factorial.” There are a variety of reasons, including change in diet and the “hygiene hypothesis,” which posits that in developed nations we are now less exposed to parasites and healthy microbes because we are more clean, we’ve used too many antibiotics (or eat animals that have), and we no longer play in the dirt as much, among other changes. This all could mean that our microbiomes — the bacteria, fungi, and viruses that are native to a healthy tummy — have also changed. And so our bodies’ immune systems have become confused. There are also indications that a predisposition toward allergies could be genetic.

As frustrating as this nondefinitive answer may be, speaking with these three doctors as a parent and journalist was grounding and clarifying. It’s no coincidence that all three of them also have children of their own who have food allergies. Knowing that we’re all in the same boat enabled me to discuss the inadequacies of the medical establishment without wanting to throttle them.

It’s hard not to feel let down as a parent of a child with food allergies. Our government and the medical establishment have made mistakes regarding food allergies in children. I’m still mad about disastrous guidance provided by the American Academy of Pediatrics (AAP) in 2000, when it saw the increase in allergies and recommended that children should not be exposed to peanuts until age three. Instead of protecting our children, the recommended abstinence appears to have had the opposite effect, causing more children to develop allergies. The AAP eventually stopped making the recommendation as allergy rates continued to rise. Clinical research led by Gideon Lack, MD, at King’s College London spurred the National Institute of Allergy and Infectious Diseases to do a complete turnaround in 2017, with the AAP’s endorsement, recommending feeding peanuts early to infants to prevent the development of allergies. (You should consult with your pediatrician regarding how you feed your child — every child is different so do not use this article as your sole source of information.) But for those of us who had children between 2000 and 2017, I guess we have to settle with a “My bad!” from the medical community.

“It was wrong. No way to spin it,” Mustafa says of the AAP’s advisory to avoid potential allergens from 2000 to 2008. “Recommendations should be based on science but the science wasn’t there.”

The fact that a decade of delayed exposure exacerbated the increase in allergies in children hurts a little bit less when I consider Mustafa’s reasoning on the subject, including that about half of knowledge in any field, not just science, is disproved or significantly changed every seven or eight years. “We don’t treat breast cancer the way we did 10 years ago,” he says. “Does that mean the people who had breast cancer 10 years ago should be pissed off? The science is always changing.”

I’m sore, but it’s not like doctors and regulators have done nothing. In 2004, Congress passed the Food Allergen Labeling and Consumer Protection Act, which determined that food manufacturers are bound to properly inform consumers if their products contain the eight major allergens. And the House of Representatives is now considering the FASTER Act, introduced by California representative Doris Matsui, which would expand research to improve the accuracy of food allergy prevalence data and also add sesame to the list of allergens that need to be labeled. The Act passed both houses of Congress last year but the House of Representatives now needs to consider revisions proposed by the Senate.

For those of us who had children between 2000 and 2017, I guess we have to settle with a “My bad!” from the medical community.

A little more than a year ago, in January 2020, the first treatment for peanut allergy, Palforzia, was FDA-approved. This is a step, but it’s no cure. It relies on the only treatment known to have any effect, immunotherapy, in which a small dose of the known allergen is fed to the patient over a period of time until, hopefully, he or she can then tolerate (but still not eat freely) a small amount of what previously could have caused anaphylaxis. Some allergists have been doing immunotherapy for peanuts for years, but Palforzia is the first time the treatment is FDA-approved. It still needs to be administered by a doctor.

I took my daughter to see a doctor who does peanut immunotherapy but decided the treatment wasn’t for us. It was too onerous (the dosing is particularly burdensome and a significant percentage of children have negative symptoms) and didn’t have enough upside (you’re only decreasing the severity of a reaction, not eliminating it). I put her through an egg food challenge clinical study at Mt. Sinai but she dropped out when she had an allergic reaction.

“It is certainly frustrating that the primary advice about food allergy has been to avoid the allergen, carry medications, and use them if needed,” says Sicherer over email. “That is why we have been constantly engaged in research to try to find better approaches.”

When families are dealt the allergy card, Mustafa believes the best approach is “shared decision-making,” which he describes as a process where the provider/allergist presents the medical information and both the provider/allergist and patient/family work together to make decisions regarding testing, treatment, management, etc. Shared decision-making stresses the importance of accounting for the child and their family’s preferences, values, goals, etc.

This tack can be very helpful when dealing with foods that come with precautionary allergen labeling (PAL) — meaning products that come with a “may contain” or “this product was made in a factory…” warning labels. There is only mild science to these labels because they are voluntary and not regulated by the government. Food manufacturers choose to put these labels on — the wording itself is also not regulated — if they believe there is any chance of cross-contact with the eight major allergens.

It puts consumers in a fearful position without really knowing what we’re afraid of. A food producer might slap on a PAL stating that its peanut-free cookies “may contain” peanuts just because the cookies have almonds in them. Almonds obviously aren’t peanuts, but because there may be some ridiculously small percentage chance that there could have been cross-contact exposure because the almonds and peanuts were stored in separate containers in a 10,000-square foot warehouse in China, I have to worry it could cause my daughter to have an allergic reaction.

I believe PALs have an exaggerated and unfair influence on the lives of people with allergies. There is no clear statistical evidence for how likely it is that a PAL-labeled food product would cause an allergic reaction. There are a few case studies, and most of them are in foreign countries. This one here cites as many as 8% of people self-reporting cases of PAL-labeled food causing a reaction. But the information is scant and incomplete. Gupta is working on one such study, which has yet to be released.

For some allergists, such as Sicherer at Mount Sinai, any chance of exposure is a reason to steer clear. “Just avoid products that have the precautionary labels, if that’s a food that you’re avoiding,” Sicherer said in a New York Times article last year under the heading, “Skip food with precautionary labels.”

That’s fine for businesses that don’t want legal problems and for doctors who don’t want their patients to ever go to the ER, but that’s not looking at the problem from a human perspective. This may be an overly dramatic comparison, but if people were advised to never get into cars because there’s a chance they might get into an accident, it sure would reduce the number of car fatalities. But then people wouldn’t be living their lives.

I think Mustafa has a more appropriate point of view when it comes to his patients, as well as to his own child with allergies. “So many of these decisions are made out of extreme fear,” he says. “But it’s not a good time to make a life decision when you are being chased in the woods.” He prefers a more reasoned-based approach to the risks: He allows his son to eat some foods with PALs, but always ensures there’s an epinephrine pen nearby.

I would never suggest any parent take unwarranted risks with their child. We have to make our own educated decisions. But since working on this article, I have become more willing to expose my daughter to foods that have some, if minor, risk of cross-contact. I recently fed her Brazil nuts for the first time. And I gave her the Fruit and Nuts granola from Bread Alone, which has a “may contain eggs” PAL on it. I called the company and spoke with its CEO, Nels Leader, who follows the guidelines from the Safe Quality Food Program, the so-called gold standard for food safety.

“I’m doing my part by providing honest and nutritious food. But I’m not going to play doctor,” he says of PALs. “You’ll have to make the best decisions for your family regarding the risk.”

The reason the granola has a “may contain eggs” labeling, Leader tells me, is because it may be baked in the same oven as the croissants, which are made with eggs. Now that I know the specific risk, I’m willing to subject my daughter to it. She tried it. She didn’t react to it. (She also didn’t exactly love it.) It sure would be helpful if every PAL came with such specific information about why there’s a risk of cross-contact, but that’s not likely to happen any time soon.

Even so, I’m now more likely to allow my daughter to eat food with an egg, or even peanut, PAL. I feel like this is the right path for her, as long as she is aware that these are all very calculated decisions that we’re making.

It is hard to determine how having an allergy affects a child’s psychology. Every child is different. My daughter takes it pretty well, but she’s certainly had to deal with life not being fair in a way that’s different from many of her peers. The other day, she told me she thinks allergies have made her think more about the ingredients in the food she eats, which has inspired her to love to cook, which we do together often.

Hopefully, this makes her stronger, more self-aware, and resilient. I do think that she has been more prepared for Covid-19 than children without allergies because she has lived her entire conscious life being aware that what seems innocuous — another kid’s snack, a kitchen counter, a muffin — can actually be a serious threat to her health.

“It’s twisted, I know,” says Pistiner, whose son, Scott, despite his allergies, is a thriving 16-year-old today. “But I can appreciate how allergies have better prepared my kid for our new age of fear.”

Culture writer; Author of THE MOST SPECTACULAR RESTAURANT IN THE WORLD [https://amzn.to/2YSavt0].

Sign up for Inside Your Head 🧠

By Elemental

A weekly newsletter exploring why your brain makes you think, feel, and act the way you do, by Elemental senior writer Dana Smith. Take a look.

By signing up, you will create a Medium account if you don’t already have one. Review our Privacy Policy for more information about our privacy practices.

Check your inbox
Medium sent you an email at to complete your subscription.

Get the Medium app