Food allergies are a growing concern in the UK, affecting millions of people of all ages. According to the NHS, a food allergy is when the body’s immune system reacts abnormally to certain foods. Unlike food intolerances, which are less severe and more common, food allergies can be life-threatening and require immediate attention.
Here, we explore what food allergies are, discuss the symptoms, and delve into the most common allergens in the UK.
What is a food allergy?
A food allergy occurs when your immune system mistakenly identifies a harmless food protein as a threat to your body. This immune response can trigger a range of symptoms, from mild to severe. Unlike food intolerances, which involve difficulty digesting certain foods, food allergies involve the immune system and can be life-threatening.
Symptoms of food allergies
Food allergies can manifest in various ways, and symptoms can range from mild to severe. According to Allergy UK, symptoms typically appear within minutes to two hours after consuming the allergen. Common symptoms include:
- Skin reactions: Hives, itching, and eczema
- Gastrointestinal symptoms: Vomiting, diarrhoea, and stomach cramps
- Respiratory symptoms: Wheezing, coughing, shortness of breath, and nasal congestion
- Anaphylaxis: A severe, potentially life-threatening reaction that includes difficulty breathing, a sudden drop in blood pressure, and loss of consciousness
Anaphylaxis is a medical emergency and requires immediate treatment with an adrenaline auto-injector – also known as an EpiPen – and emergency medical assistance.
Types of food allergies
There are three main types of food allergies, categorised by the type of immune response they trigger:
- IgE-mediated food allergies: This is the most common type of food allergy, where the immune system produces immunoglobulin E (IgE) antibodies in response to an allergen. Symptoms typically occur within minutes of exposure and can lead to anaphylaxis.
- Non-IgE-mediated food allergies: These allergies do not involve IgE antibodies. Instead, other components of the immune system are activated, leading to symptoms that are often delayed by several hours or even days. Common symptoms include gastrointestinal issues such as vomiting, diarrhoea, and constipation.
- Mixed IgE and non-IgE-mediated food allergies: Some people may experience symptoms from both IgE-mediated and non-IgE-mediated reactions. For example, a child with a cow’s milk allergy might have immediate symptoms, such as hives (IgE-mediated) and delayed symptoms, such as diarrhoea (non-IgE-mediated).
Food allergy testing and diagnosis
Diagnosing a food allergy involves a combination of your medical history, a physical examination, and diagnostic tests. According to NHS guidelines, the most common methods of testing for food allergies include:
- Skin prick test: A small amount of the suspected allergen is placed on the skin, and the skin is pricked to allow the allergen to enter. A positive reaction, usually a raised bump, indicates a possible allergy.
- Blood test: A blood sample is taken to measure the level of IgE antibodies to specific allergens.
- Oral food challenge*: Under medical supervision, the patient will consume small amounts of the suspected allergen to monitor for a reaction. This is considered the most definitive test, but carries the risk of a severe reaction.
*Warning: It is crucial that food allergy testing should always be conducted under the supervision of a healthcare professional, to ensure accurate diagnosis and to manage any potential reactions.
Treatment and management of food allergies
The primary treatment for food allergies, unsurprisingly, is strictly avoiding the food you are allergic to. However, accidental exposure can still occur, so many people with known food allergies often carry an adrenaline auto-injector (such as an EpiPen) at all times. The NHS recommends that those with severe allergies should wear medical alert bracelets and inform those around them—friends, family, teachers, and colleagues—about their condition.
For those with mild to moderate allergies, antihistamines can help alleviate symptoms. In some cases, allergen immunotherapy (desensitisation) may be considered. This involves gradually introducing small amounts of the allergen to the patient to build tolerance over time, which can reduce the severity of reactions.
The top 14 allergens in the UK
The Food Standards Agency (FSA) has identified 14 allergens that are responsible for the majority of food allergies in the UK:
- Celery
- Cereals containing gluten (wheat, rye, barley, oats)
- Crustaceans (e.g. crab, lobster)
- Eggs
- Fish
- Lupin
- Milk
- Molluscs (e.g. mussels, oysters)
- Mustard
- Nuts (e.g. almonds, hazelnuts, walnuts)
- Peanuts
- Sesame seeds
- Soya
- Sulphur dioxide and sulphites (used as preservatives)
The allergens above must be clearly identified on food packaging in the UK, as per the EU Food Information for Consumers Regulation (1169/2011). Even small traces of these allergens can trigger a reaction in someone with an allergy.
It’s more common than you think
Food allergies are increasingly common in the UK, with more than 2 million people living with a diagnosis. Around 5-8% of children are affected, while the prevalence in adults is slightly lower, at around 1-2%. The most common allergens – milk, eggs, peanuts, tree nuts, and fish – are the cause of the vast majority of allergic reactions.
Food labelling legislation in the UK
The UK has strict food labelling laws to protect consumers with food allergies. The FSA enforces these regulations, which require food businesses to clearly list any of the 14 allergens present in their products. This includes pre-packaged foods, as well as foods sold in restaurants, cafes, and takeaways.
Since the implementation of Natasha’s Law in October 2021, businesses are now required to provide full ingredient and allergen information on foods pre-packed for direct sale (PPDS). This law was introduced following the tragic death of Natasha Ednan-Laperouse. The law aims to prevent such incidents by ensuring that consumers have access to clear information about the food they are eating.
The importance of education and awareness
Given the severity of food allergies, it is crucial that parents, GPs, teachers, and employers are educated about the risks. Awareness can save lives.
Parents should be vigilant in monitoring their children’s diet and educating them about their allergies from a young age. Teachers and school staff should be trained in recognising allergic reactions and administering emergency treatment, such as using an EpiPen.
Healthcare professionals play a critical role in diagnosing and managing food allergies. It is also important for employers to ensure that their workplace is safe for employees with food allergies, and communicate clearly about allergens present in communal areas.
Conclusion
Food allergies are a significant health issue in the UK, requiring careful management and widespread awareness. With millions of people affected, it is essential that everyone understands the risks and takes appropriate steps to protect those around them. The combination of strict food labelling laws, effective management strategies, and public education can help reduce the incidence of allergic reactions and improve the quality of life for those living with allergies.
If you have been experiencing any of the symptoms listed, please contact your Primary Care 24 GP practice and make an appointment to discuss this further with your doctor.
