Multi-Food Allergies: New Research On Their Impact

A 2022 study explores how common multi-food allergies are, the most frequent food allergy patterns in people with multiple food allergies, and burdens that people with multiple food allergies face. Learn about the most important findings of this study for families.

Although there have been some studies on the estimated percentages of people with multiple food allergies, a lot of questions have remained about living with more than one food allergy.

A new study explores how common multi-food allergies are, which food allergy patterns tend to show up together, and the increased burdens that people with multiple food allergies face. Today, we’ll break down the most important findings of this study for families.

The multi-food allergy study: A closer look

A 2022 study, conducted by Dr. Christopher Warren, Dr. Ruchi Gupta and others at the Center for Food Allergy and Asthma Research (CFAAR) in Chicago, explored the prevalence and burdens of living with more than one food allergy. It also examined common patterns of food allergies that tend to show up together.

One of the most surprising findings is just how many food allergic individuals have allergies to multiple foods.

Out of the people in the study who have at least one “convincing” IgE-mediated food allergy (who have shown at least one food allergy symptom on a list developed by an expert panel), 40% of children have multiple food allergies, and 46% of adults have multiple food allergies.

But what challenges does living with multiple food allergies pose? And are there certain groups of food allergies that tend to occur together?

Let’s break down key elements of the study below.

Who was involved in the study?

40,443 adults and 38,408 children in the U.S., who completed a survey

  • 7.6% of these children, and 10.8% of these adults, reported having a “convincing” IgE-mediated food allergy to at least one food (based on a list of food allergy symptoms developed by an expert panel)

What percentage of the people with convincing food allergies had multiple food allergies (multiple FAs)?


Note: If someone had allergies to more than one tree nut, more than one finned fish, or more than one shellfish, this counted as having multiple food allergies.

  • 40% of children with convincing IgE-mediated food allergies reported multiple FAs
    • 33% of children under the age of 3, with convincing IgE-mediated food allergies, reported multiple FAs
    • 40% of children 3 years of age and older, with convincing IgE-mediated food allergies, reported multiple FAs
  • 46% of adults with convincing IgE-mediated food allergies reported multiple FAs

What percentage of all the people surveyed had more than one convincing food allergy?

Children: 3% had multiple food allergies

  • 1.8% of all the surveyed children had two or three convincing food allergies
  • Another 1.2% had more than three convincing food allergies

Adults: 4.8% had multiple food allergies

  • 3.1% of all the surveyed adults had two or three convincing food allergies
  • Another 1.7% had more than three convincing food allergies

Were there patterns in the food allergies that tend to show up together?

Yes. In both the children and the adults with food allergies, four patterns were found:

  • Milk and egg allergies
    • Around 51% of children, and around 55% of adults, had higher probabilities of these food allergies
    • Peanut and tree nut allergies
      • Around 28% of children, and around 17% of adults, had higher probabilities of these food allergies
      • Shellfish and finned fish allergies
        • Around 16% of children, and around 24% of adults, had higher probabilities of these food allergies
        • Broad multi-food allergies
          • Around 5% of children, and around 4% of adults, had a higher probability of allergies to at least two of the top 9 food allergens

        Did multiple food allergies mean a higher likelihood of severe reactions?

        Yes. Both children and adults with multiple food allergies were more likely to have had a severe allergic reaction.

        Also, adults with two to three food allergies were twice as likely to have a prescription for an epinephrine auto-injector (EpiPen), compared to those with only one food allergy.

        Adults with four or more food allergies were three times as likely to have an EpiPen prescription.

        Children with two or more food allergies were also more likely to have a prescription for an EpiPen vs. those with only one food allergy. (Rates were similar to those seen in adults.)

        This is significant because epinephrine is the only medicine that can stop a severe allergic reaction.

        Were people with multiple food allergies more likely to have needed emergency care?

        Yes. The more food allergies someone has, the higher the likelihood that they visited the emergency room in the past 12 months for food allergy-related care.

        Children:

        • 24.6% of children with 2-3 food allergies visited the emergency room at least once within the 12 months before the survey.
        • 30.5% of children with over 3 food allergies visited the emergency room at least once within the 12 months before the survey.
        • That’s compared to almost 14% of the children with only one food allergy.

        Adults:

        • 9.6% of adults with 2-3 food allergies visited the emergency room at least once within the 12 months before the survey.
        • About 19% of adults with over 3 food allergies visited the emergency room at least once within the 12 months before the survey.
        • That’s compared to 5% of the adults with only one food allergy.

        Were there any other significant findings?

        Compared to people with one food allergy, people with two or more food allergies were also more likely to have related conditions, such as eczema, GI issues, asthma, and environmental allergies.

        In addition, people with more than one food allergy reported feeling a higher perceived burden related to food allergies.

        Breaking down the findings

        This study was the first to examine the prevalence of multiple food allergies based on a large segment of the general population. It shows that a lot more people are dealing with multiple food allergies than both the allergy community and the public expected.

        The study also found that children and adults with multiple food allergies were more likely to:

        • Have experienced a severe food allergy reaction
        • Have received emergency care for a food allergy reaction
        • Carry epinephrine
        • Be diagnosed with related conditions
        • Feel like they carry a high psychological/social burden due to their food allergies

        These findings show that, while having one food allergy is already hard, having multiple food allergies places an even more difficult burden on children and adults.

        People with multiple food allergies must avoid more than one type of food ingredient to keep themselves safe. If they’re accidentally exposed to even a small amount of any of their allergens, they will develop an allergic reaction that could become severe. This can often cause higher stress levels around finding safe foods and eating, which can lead to a more negative quality of life.

        Given that rates of multiple food allergies are higher than the researchers expected, this underscores the importance of detailed allergist care to help reduce this burden. Allergists need to develop new strategies for managing, and possibly treating, multiple food allergies.

        And along with allergist care, awareness of the possible mental burdens is vital, so people with multiple food allergies can access mental health resources if needed.

        Since the study shows that multiple food allergies also tend to follow patterns, this means that someone with a peanut allergy, for example, is likely at higher risk for a tree nut allergy.

        Knowing this could make food allergy diagnosis more efficient, so people can receive the needed management guidance faster. It could also be helpful in developing future food allergy management and treatment strategies, to help reduce the overall burden of living with multiple food allergies.

        What does this mean for parents?

        If you suspect that your child has any food allergy, allergist care is crucial. But if your child shows signs of having multiple food allergies, it’s even more vital to take them to an allergist. The allergist can help you develop a plan for managing multiple food allergies, including finding safe foods and knowing which foods to avoid. Plus, an allergist might be able to inform you about emerging food allergy treatments, and/or direct your child to mental health resources if needed. This guidance will help reduce the burden that you and your child may experience due to their multiple food allergies.

        Introduce Allergens Safely and Easily with Ready. Set. Food!

        All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

        These statements have not been evaluated by the Food and Drug Administration. Products are not intended to diagnose, treat, cure or prevent any disease.  If your infant has severe eczema, check with your infant’s healthcare provider before feeding foods containing ground peanuts.