There has been a dramatic increase in the amount of food allergy over the past 20-30 years. Once considered unusual, it now affects 6-8% of young children in the UK and around 1-2% of adults.
There are many different forms of food allergy, some life threatening, others not. A diagnosis of food allergy can have a massive impact on the everyday life of both a patient and their whole family. It is essential for optimal management that all the problem foods are correctly identified and that patients know exactly how to recognise and treat allergic reactions if they occur. It is also important that the common allergic problems such as eczema and asthma, that commonly go hand in hand with food allergy, are identified and treated.
It is becoming increasingly apparent that food allergy may present not only with obvious reactions such as hives or swelling immediately after eating the problem food. Allergy, particularly in smaller children, may present with a wide variety of different problems including:
- Gastro-oesophageal reflux (effortless vomiting usually after feeds)
- Poor weight gain
Until the underlying allergy is identified and removed, the symptoms may progress and worsen despite aggressive use of treatments such as steroids or other medications.
Food allergy may develop in adult patients as a new problem or may be a continuation of allergies that developed in childhood. Although childhood food allergies will often resolve (especially milk, egg and wheat) some are more inclined to persist (e.g. nuts, sesame, fish, shellfish).
Reassessment of such food allergies can sometimes identify foods that can be safety reintroduced back in the diet. The most common adult food allergies are to fresh fruit and vegetables in people with pollen allergy (known as Pollen Food Syndrome). Adults who have experienced a severe allergic reaction (such as anaphylaxis) should be evaluated by an Allergist, who will consider food allergy as a potential cause. There are many foods which may trigger such new reactions although the most common are seafood, nuts, seeds and fruit/vegetables. In some cases, food allergic reactions only occur when the food is eaten before exercise (Food-Dependent Exercise Induced Anaphylaxis). Therefore anaphylaxis in adults requires assessment with a careful history followed by test to identify the potential culprit. Sometimes this will involve molecular diagnostic testing.
Adults with eczema may also have undiagnosed food allergies, although this is less common than in children. Sometimes identification of such allergies can help improve eczema symptoms.
A careful, detailed clinical history taken by an experienced physician coupled with allergy tests such as skin prick testing, specific IgE blood testing, atopy patch testing or provocation challenges remains the most reliable way to reach a diagnosis or exclude allergy as the cause of the problems.
Whilst standard advice in the NHS is to avoid food allergens, there is also another approach known as desensitisation or OIT (Oral Induction of Tolerance). This is a newer approach to food allergies such as milk, egg and peanut that now has a solid scientific grounding and is an area of particular interest at Allergy London. To find out more click here or contact us.
We offer this as well as ongoing holistic care to ensure that food allergy has as little impact as possible on day to day life. This includes working in partnership with expert allergy dieticians.
Food allergies can be daunting, especially for parents with a baby or child who is a sufferer. To help parents with children with food allergies, Prof Fox has written a definitive guide to managing your child’s food allergy, ‘The Allergy Free Baby & Toddler Book’ available on Amazon.
Prof Fox has also spoken to The Today Programme on the topic of food allergies.