Food allergies occur when the body’s immune system reacts to certain proteins in food. Allergic reactions to food vary from mild to life-threatening symptoms. There’s currently no cure for food allergies.
A food allergy is essentially “the immune system mistaking an otherwise harmless food for something that’s potentially dangerous,” says Dr. David A. Hill, a pediatric allergist at the Children’s Hospital of Philadelphia and an assistant professor of pediatrics at the University of Pennsylvania.
Food allergies affect millions of children, but researchers are beginning to see signs of progress. After years of rising diagnosis rates, new evidence, including a recent study led by Hill, suggests that introducing common sources of food allergies in the first year of life is associated with reductions in new cases of food allergies in children.
Yet prevention is only part of the story. For families already living with food allergies — and for clinicians and policymakers trying to keep them safe — the challenge remains in understanding why allergies persist, how best to treat them, and how to close the gaps in care and protection.
“I really want people who already have food allergies, children and adults, to know that we haven’t forgotten about them,” Hill says. “And even though it’s important to have this important preventative option available, it’s really a reminder that we also need to double down and understand why food allergies persist and how we can move towards more effective treatments and cures.”
For those of you covering food allergies, we’ve gathered some of the research and data to inform your reporting. Below, we address the following questions:
How common are food allergies?
There are several different types of food allergies.
The most common food allergies are considered IgE-mediated, driven by the immune system’s proteins called immunoglobulin E, or IgE. These antibodies react to harmless food proteins as if they were threats. As a result, the body releases chemicals like histamine, which cause allergy symptoms like hives, swelling or trouble breathing.
The prevalence of food allergy in U.S. children ranges between 6% to 8%, according to studies in the past decade.
Parent-reported food allergy prevalence in U.S. children younger than 18 years was 5.6% in 2012 and 5.8% in 2021, according to the Centers for Disease Control and Prevention’s National Health Interview Survey, which includes as many as 40,000 children 0 to 17 years old annually. That’s about 1 in 17 children. (In comparison, about 1 in 5 children had a seasonal allergy, 1 in 10 had eczema (also called atopic dermatitis), according to the 2021 survey.)
A large, nationally representative survey of U.S. households conducted between 2015 and 2016, published in the journal Pediatrics in 2018, estimated the overall prevalence of food allergies among children to be 7.6%. That’s about 5.6 million children under 18. In the same survey, 11.4% of children’s caregivers reported a current food allergy, before researchers filtered out cases that lacked a convincing history of IgE-mediated food allergy. This suggests that the perceived rates of food allergy may be greater than the clinically confirmed rates.
And, an earlier report based on the 2007-2010 National Health and Nutrition Examination Survey, including 20,686 people, found the self-reported prevalence of food allergy in children to be 6.53%, according to a 2014 study.
Estimates for the prevalence of food allergies vary, partly because studies use different methods, may include different geographic areas or use different definitions of food allergy, according to a 2014 study published in the journal Immunology and Allergy Clinics of North America.
For instance, terminologies such as allergy, hypersensitivity, pseudo-allergy and intolerance are often incorrectly used interchangeably, which can lead to confusion in food allergy research and data collection, according to a 2022 study published in the World Journal of Clinical Pediatrics. For instance, in contrast to food allergies, food intolerance does not involve the immune system.
Some food allergy studies also rely on patient or parent reports, which can be subjective and overestimate true food allergy rates. In addition, it’s difficult to know the specific forms of food allergies from parent-reported surveys and studies, compared with studies that rely on electronic health records.
In Europe, a 2023 systematic review and meta-analysis of 110 studies found that when the estimates of studies that included self-reported food allergy data were pooled together, 18% of children had a food allergy at some point in their lives. But the estimates of studies that collected self-reported data based on a physician diagnosis, the prevalence of food allergies among children was 9%.
The rate of self-reported food allergies has risen by 1.2% per decade since 1988, with an economic burden of nearly $25 billion each year, including medical costs and parents’ lost work hours to accompany children to medical visits, according to a 2022 study published in the journal Immunotherapy Advances.
Nearly 1 in 5 children with food allergies go to the emergency room for an allergic reaction, said Dr. Ruchi Gupta in a 2023 video presentation during the sixth annual Children’s National Hospital-NIAID Symposium. Gupta is a professor of pediatrics at Northwestern University and the founding director of the Center for Food Allergy & Asthma Research.
Researchers believe several factors are driving the increase in food allergies, including “complex interactions between genetic and environmental factors, including growing adoption of a westernized lifestyle globally, and changes to infant feeding practices in recent decades,” according to a 2024 study published in the journal Current Allergy and Asthma Reports.
Worldwide, around 4% of children and 1% of adults have food allergies, with an increased prevalence in the past two decades, according to a 2022 study published in the World Journal of Clinical Pediatrics.
But global estimates vary and not all countries collect food allergy data.
A 2013 study published in The World Allergy Organization Journal found that more than half of the 89 countries surveyed did not have any data on food allergy prevalence. Researchers have called for improvements in the design of studies and diagnostic tools.
What are the most common childhood food allergies?
The most common food allergies are known as the “Big 9”: milk, eggs, peanuts, tree nut, soy, wheat, fish, shellfish and sesame. They account for 90% of food allergies in the U.S.
A 2016 nationally representative survey of 38,408 U.S. children found that peanut allergies were most common (2.2%), followed by milk (1.9%), shellfish (1.3%), tree nut (1.2%) and egg (0.9%). The results were published in a 2018 study in the journal Pediatrics.
But the recent study led by Hill finds that recent guidelines that encourage parents to introduce infants to food products like peanuts have pushed peanut allergy from first to second most common food allergy in children younger than 5, behind egg.
Milk and egg allergies usually resolve in children as they get older, while peanut, tree nut and shellfish allergies are usually lifelong, said Gupta during her 2023 video presentation.
How are food allergies diagnosed?
Diagnosing food allergies is a multi-step process, combining clinical history with various tests.
“The most important information in making a food allergy diagnosis is the history of the food-related reaction,” Hill explained by email. “If the history is not consistent with a food allergy, testing is not recommended.”
These are some of the current and emerging food allergy tests:
The most common food allergy test is a skin prick test. Allergen extracts are placed on the skin and scratched with a lancet. The swelling is measured after 15 minutes. A swelling of 3 millimeters or more indicates a possible clinical allergy.
Another common test is a blood test measuring specific Immunoglobulin E (sIgE) in the serum.
The Oral Food Challenge is the gold standard in food allergy testing. It’s a double-blind placebo-controlled test to confirm or rule out food allergy when the patient’s reported allergic history is inconsistent with the results of skin prick tests and blood tests. The patient eats small doses of the suspected allergens during the test. The test is time and staff-intensive and requires a physician, nurse and rescue medication, and as a result not available to all patients.
Component Resolved Diagnostics is an emerging tool that can measure IgE antibodies to specific proteins within an allergen, like peanut. The test enables physicians to create a more individualized treatment plan.
The Basophil Activation Test is another emerging method that measures how a person’s basophils — a type of white blood cell involved in allergic responses — react when exposed to food allergens. The test is described as an oral food challenge in a test tube, but the test is still restricted to research laboratories.
What are the available treatments?
Two food allergy medications are approved by the Food and Drug Administration in the U.S.
The FDA approved omalizumab (Xolair) injection in 2024 for children older than one with one or more food allergies. The drug reduces the risk of severe allergic reactions from accidental exposure to food allergens.
Peanut (Arachis hypogaea) Allergen Powder-dnfp (Palforzia) oral immunotherapy, for children 1 to 17 years old, reduces the risk of allergic reaction to peanuts. It was approved by the FDA in 2020.
Several other therapies are currently under investigation, according to Food Allergy Research & Education, or FARE, a nonprofit organization focused on food allergies.
The main emergency treatment for severe food allergy reactions is epinephrine, available as an injection and nasal spray.
What can increase the risk of developing food allergies?
Researchers are still trying to understand why some people develop food allergies while others don’t. Evidence-based research points to several factors that increase a person’s risk of developing food allergies.
Eczema: Children with moderate to severe eczema have a greater risk for food allergies than children who have mild or no eczema. “With skin inflammation like eczema, it’s much easier for things in the outside world to get into the skin, and in particular, that can happen with food proteins,” Hill explains. Studies indicate that the immune system may attack food allergens absorbed by the skin, leading to food allergy.
Genetics: A 2019 NIAID-funded research found that kids who had certain genes were much more likely to develop peanut allergy than kids who didn’t. There are also ongoing clinical trials investigating the genetic and immunologic pathways that lead to the development of food allergies.
Changes to the microbiome — the community of tiny organisms living in and on our bodies — caused by a variety of factors, including:
Exposure to antibiotics early in life can change the microbiome. Infants are more likely to receive antibiotics in the first year of life, which can change their microbiome.
Births by cesarean section. Some studies suggest that babies born by C-section have a higher risk of developing food allergies, noting that the babies don’t get exposed to their mothers’ vaginal microbiome, which affects the development of the babies’ microbiome. NIAID is funding clinical trials to further study this association.
Insufficient vitamin D: A 2013 study published in the Journal of Allergy and Clinical Immunology, and based on a sample of 5,276 infants born in Australia, offered some of the first evidence that sufficient levels of vitamin D in babies may protect against developing food allergies in the first year of life. However, a 2020 review of 24 published studies found contradictory data on the relationship between vitamin D deficiency and the development of food allergies. Researchers have called for an urgent need for well-planned randomized controlled trials to further investigate this relationship.
Urban living: U.S. children living in rural communities have the lowest rates of food allergies compared with children who live in urban and suburban areas or small towns, studies find, including a 2012 study published in the journal Clinical Pediatrics.
Can peanut and other food allergies be prevented?
A growing body of evidence in the past decade shows that introducing foods like peanut products and eggs to infants’ diet can prevent them from developing food allergies in childhood.
In 2015, the landmark Learning Early About Peanut (LEAP) study — a randomized, open-label, controlled trial of 640 infants in the United Kingdom — showed that giving children foods with peanut before their first birthday, between 4 and 11 months of age, drastically reduced their risk for having peanut allergy by the time they were 5 years old. (Unlike blinded trials, in open-label trials researchers and participants know which treatment each person is receiving.)
Children who had started eating peanut products as infants were 81% less likely to develop a peanut allergy compared with children who had avoided eating peanut products until age 5, the LEAP study showed.
Shortly after the publication of the LEAP trial, AAP changed its recommendation, encouraging early introduction of peanut products in infant foods.
A 2016 follow-up study to the LEAP trial, Persistence of Oral Tolerance to Peanut (LEAP-On), showed that children who were given peanut foods regularly as babies until age 5 were much less likely to develop a peanut allergy, even after they completely avoided peanuts for a year, compared with children who had always avoided peanuts.
The National Institute of Allergy and Infectious Diseases convened an expert panel to update its guidelines, leading to the 2017 Addendum Guidelines for the Prevention of Peanut Allergy in the United States, recommending the introduction of peanut-containing food for infants with severe eczema, egg allergy or both, between 4 to 6 months of age. They also recommend the introduction of peanut-containing food to infants with mild to moderate eczema around 6 months of age.
In 2021, the American Academy of Allergy, Asthma, and Immunology, American College of Allergy, Asthma, and Immunology, and the Canadian Society for Allergy and Clinical Immunology issued a consensus report for the prevention of food allergy, recommending the introduction of peanut products and egg around 6 months of age, but not before 4 months. The guidelines emphasize shifting from avoiding allergenic foods to introducing them early and diversely.
In October, Hill and his co-authors published the first, large-scale U.S. study investigating the real-world impact of the guidelines, outside of the clinical trial settings.
Their analysis of 124,868 children across 50 pediatric practices in the U.S. shows that newly diagnosed cases of peanut allergy dropped by 43% in children under 3, when researchers compared the cohort of children before the guidelines to the cohort after the guidelines. Overall, there was a 36% reduction in all new cases of food allergies.
“If this trend continues over the next decade, we’re going to see, hopefully, overall food allergy rates coming down,” Hill said.
The study does have limitations. For instance, researchers didn’t collect data on what the infants ate — when specific foods were introduced, how much and how often — so the study doesn’t show that the guidelines directly caused the decline in food allergies. However, experts have found the results promising.
What are local, state and national policies to protect children with allergies?
For the first time in 2013, the CDC issued the “Voluntary Guidelines for Managing Food Allergies in Schools and Early Care and Education Programs,” which provides a set of voluntary best practices for schools and child care to follow.
Some of the main priorities of the guidelines include identifying students with allergies, training staff to recognize and treat severe allergic reactions, teaching children and parents about avoiding allergens, and reducing allergen exposure in cafeterias, classrooms, buses and extracurricular activities.
Several states have also issued guidelines for school food allergy management, a list of which is available on Food Allergy Research & Education’s website.
Some states have also passed laws.
In 2019, New York signed Elijah’s Law into law, requiring child care programs to follow guidelines for preventing and responding to severe food allergy reactions, according to AAFA. The law has also been passed in Illinois and introduced in California, Pennsylvania and Virginia. The law is named for a child who died after having a severe allergic reaction at his preschool.
California signed Zacky’s Bill into law in 2022, requiring the State Department of Education to create the California Food Allergy Resource website, providing voluntary guidance to school districts, county offices of education and charter schools about the importance of food allergy management and treatment. The law is named after a child who has life-threatening food allergies.
A 2025 report by the nonprofit Asthma and Allergy Foundation of America finds that while most states have policies to support students with allergies and asthma, significant policy gaps remain. The report offers several recommendations, including expanding emergency medication stocking in schools and ensuring full-time nurses in every school.
Journalists can check for several measures at the local level:
Review your school district’s policy on food allergies. Does it require training for all staff? Does it have epinephrine in stock?
Do schools use written, individualized care plans for allergy management?
Do cafeterias and classrooms have protocols to prevent cross-contamination and to manage allergens?
Do schools seek input from families regarding their child’s allergies, and do they promptly respond to incidents of allergic reactions?
How do food allergy rates differ by race and income?
Studies show that non-white children and those in lower-income families have higher rates of food allergies.
A 2020 study published in the Journal of Allergy and Clinical Immunology In Practice finds that Black, Hispanic, and lower-income families bear a greater burden of food allergies, yet often have less access to diagnosis, specialty care and preventive resources.
In addition, Black patients are 30% to 40% more likely to report emergency department visits due to severe food allergy reactions compared with white patients, even after accounting for income and education, the study finds.
Some of the underlying drivers are linked to social determinants of health, including income, insurance type, neighborhood environment and structural racism.
The 2021 NHIS survey found that Black children were more likely than white and Hispanic children to have a food allergy. Overall, 7.6% of the Black children reported a food allergy, compared with 5.3% of white children and 5% of Hispanic children in the survey.
Implementation of early introduction of food allergens in physician practices is also not uniform, as studies in 2020 and 2024 have found. And not all parents are taking up early introduction of peanut products and egg to their infants.
“There may be parts of the country where implementation of the early introduction is much lower, and in which case, we would expect to see a lower effect of that public health recommendation in those areas,” Hill says. “But it’s certainly very encouraging that if nationally we have similar implementation rates or better implementation rates, that we can have a real impact on new onset food allergy moving forward.”
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