In part one of our Academic Blog Series for Food Allergy Awareness week Dr Béré Mahoney, from the School of Psychology, leads a team of University of Worcester researchers who are exploring what is it like psychologically for adults living with the severest of allergic reactions or anaphylaxis. Here, Dr Mahoney along with team members Professor Eleanor Bradley, Director of Research for Health and Science, and Dr Steve O’Hickey, Honorary Professor and Consultant Physician at Worcestershire Acute Hospital NHS Trust, discuss what food allergy is and what is it like living with one.
What is a food allergy?
Allergy is a condition in which the immune system can be the body’s enemy rather than its ally. The term allergy was coined in 1906 by Viennese paediatrician Clemens von Pirquet, now regarded by many as the founder of modern immunology [1]. At that time, his ideas were at odds with dominant medical thinking that the body’s immune system is protective [2]. Pirquet and colleagues’ clinical observations showed some individuals are in fact hypersensitive to their body’s immune response. They used the term allergy (derived from the Greek allos meaning other, different, strange) to describe this severe and unusual immune reaction to what they termed allergens. Medical and popular attention to both allergy and allergens has a considerable history.
Claims of severe food allergy were described in the writings of the ancient Greeks and Romans, with suggestions (much contested) that King Richard III was deliberately poisoned by strawberries [1].
Today in the UK and other western countries, much of the work in allergy clinics involves diagnosing and treating individuals with food allergy, along with other forms of allergy such as asthma, hay fever, and reactions to drugs or venoms such as bee or wasp stings. In his work at the Allergy Clinic run by Worcester Acute Hospitals NHS Trust, Professor O’Hickey has found that popular understanding about food allergy is not good. Here are some better and lesser known facts about the condition:
Better Known Allergy Facts:
- food allergy is a profound hypersensitivity reaction provoked by a food or foods
- the substance that triggers the allergic reaction is called an allergen and often it is a small or specific part of a food that can cause this
- among the most common allergens are milk, egg, peanuts, sesame seeds, kiwi fruit, fish, shellfish, tree nuts, wheat and soy
Lesser Known Allergy Facts:
- in some cases an allergen can be altered by cooking
- any foods can be an allergen and trigger an allergic reaction
- food (and any) allergy can change as the individual ages - you can ‘grow out’ of a particular allergy although often this will be replaced by another allergy
- the incidence of food allergy varies geographically, for example peanut allergy is almost unheard of in Israel
- the likelihood of having food allergy depends on many factors but genetics play a part
What is the difference between a food intolerance, allergy and potentially life-threatening allergic reaction?
According to Allergy UK the UK has some of the highest prevalence rates for allergies in the world. However, greater public awareness around these issues is not matched by better public understanding of the differences between food intolerance, allergy, and severe life-threatening allergic reactions.
In the USA a recent survey of over 40,000 adults found that among respondents around 19% claimed to have a food allergy when in fact only 11% had what they called a ‘convincing’ food allergy –one that had been diagnosed by a medical doctor [3]. Clearly, identifying the prevalence of food allergy is problematic, especially when we rely on individuals’ self-reports of having an allergy.
Reports are often shaped by psychological factors such as common-sense beliefs about health, food and the meaning of the terms sensitivity, intolerance and allergy.
Exploring psychological factors is central to current debates about whether the food allergy ‘explosion’ is real or in part the result of greater public awareness and (mis)understanding of allergy [4]. According to the British Society of Allergy and Clinical Immunology, food allergy and food intolerance are both forms of food hypersensitivity reactions but have important differences:
|
|
Food intolerance | Food allergy |
| How common is it? |
Around 20% of the population report altering their diet because they believe they are intolerant
|
Around 4% of adults and 6 - 8% of children are diagnosed with some type of allergy
|
|---|
| Does it involve the immune system? |
No
|
Yes
|
|---|
| What are the symptoms like? |
Less severe
|
Severe, and potentially life-threatening for some at risk of anaphylaxis (severest reaction)
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|---|
| How quickly does someone react to the trigger food allergen? |
Typically, within hours and up to several days after eating it
|
Typically, within 1 hour of eating it
|
|---|
Conclusion
So, in Part One of our Food Allergy Awareness blog posts we understand what food allergy is, how intolerances and allergies differ and that psychological factors can influence this. In Part Two of our series we will learn about our Psychological research into food allergy, how people can be diagnosed and its effect on our lives and how food allergies differ from those to wasp sting or prescription drugs.
Psychology research at the University of Worcester seeks to address some of the major issues in professional life, personal experience, our community and beyond it. Research opportunities are available to students and our Psychology BSc can enable you to discover research methods, use our facilities and learn from our academics to suppost their interests.
All views expressed in this blog are the Academic’s own and do not represent the views, policies or opinions of the University of Worcester or any of its partners.