Allergic reactions to Quorn products are usually caused by an allergy to its mycoprotein content – a fungal protein derived from the fungus Fusarium venenatum. The information provided here is aimed at people who are allergic to Quorn, or think they may be allergic, so that they can better understand their symptoms and are able to ensure they have the appropriate treatment.
In some cases, allergic reactions to Quorn could be caused by other ingredients of the product such as egg, milk or wheat. It is important to obtain good medical advice to determine exactly what caused your symptoms.
Marlow Foods, the manufacturers of Quorn products, have told us that mycoprotein is found only in Quorn branded products, not in any other food products on the UK market.
Symptoms of food allergy
The symptoms of food allergy can come on rapidly. These may include nettle rash (otherwise known as hives or urticaria) anywhere on the body, swelling around the mouth or eyes (known as angioedema) or a tingling or itchy feeling in the mouth.
Many people’s allergy symptoms are mild but on rare occasions serious symptoms occur. These most commonly include:
- Swelling in the throat
- Difficulty breathing
- Severe asthma
- Severe abdominal pain, nausea and vomiting
The term for this more serious form of allergy is anaphylaxis. In extreme cases there could be a dramatic fall in blood pressure (known as anaphylactic shock). The person may become weak and floppy and may have a sense of something terrible about to happen. This may lead to collapse and unconsciousness. On rare occasions, death can occur.
See the links at the end of this article for more details about anaphylaxis and its treatment.
Diagnosis of Quorn allergy
We recommend that you see your GP if you suspect that you may have an allergy to Quorn. Your GP may refer you to an allergy clinic where skin prick tests or blood tests may be performed as part of your diagnosis.
Treatments for Quorn allergy
It is vital to ask your doctor about the symptoms that are likely to occur in your own individual case so that you are clear about what treatment must be given.
Antihistamines can be used to treat mild allergic reactions. However, in rare cases anaphylaxis may occur and if your doctor believes this is a risk he or she is likely to prescribe an adrenaline auto-injector device. The auto-injector should be used as soon as a serious reaction is suspected. In all cases of anaphylaxis, someone should dial 999, irrespective of whether an auto-injector is available or not.
Antihistamines cannot be relied upon to treat anaphylaxis, even if the symptoms are in their early stages. Oral antihistamine treatment delivers no measurable activity within 30 minutes of the dose, and peak activity is not reached for about three hours. Adrenaline is always the first line of defence in the treatment of anaphylaxis.
Ingredients of Quorn
Quorn products contain a variety of ingredients other than mycoprotein. Some contain other potential allergens such as egg, milk and wheat. Allergy tests will help determine whether one of these may be the cause of your allergy instead of mycoprotein.
There are low levels of lactose in most Quorn products so they may be unsuitable for people who are lactose intolerant.
The key message is always read the ingredient list.
What else might I react to?
People who are allergic to Quorn may also suffer allergy symptoms when they are exposed to mould spores. This is because of a process called cross-reactivity – where the proteins in one food or substance share potential allergenic characteristics with those in another food or substance.
Researchers reported the case of a nine-year- old girl who suffered generalised nettle rash, asthma and abdominal pain a few minutes after eating Quorn in a canteen. The study team found she was allergic to both Quorn and mould. They concluded:
“Physicians should be aware that Quorn mycoprotein may cause food allergic reactions in mould-sensitised patients and should think of this allergen especially in vegetarian people.” (Morel-Conreanu et al, 2015)
If you are sensitised to mould, it is important to remember that it can form anywhere: from window frames to decaying food. Try to reduce your exposure if possible.
Precise statistics are not available. Based on our experience and on the knowledge gained via our helpline, we believe that allergy to Quorn is rare in the UK and this is supported by members of our clinical panel.
It may not be allergy
Many people who believe that Quorn is causing unpleasant physical symptoms may not actually have an allergy.
In January 2011 Marlow Foods, the company that makes Quorn, convened a one-off independent expert panel in London to discuss consumer reports of adverse symptoms caused by mycoprotein. Panel members comprised respected international experts including Prof. Steve Taylor, Director of the Food Allergy Research and Resource Program in Nebraska, USA. The panel concluded:
“The number of reported adverse reactions to mycoprotein is very low and it is likely that most of these incidents relate to the high fibre content. Mycoprotein provides around 5.5g of dietary fibre in 100g of Quorn mince or pieces. The Panel hypothesised that, in certain individuals or under certain conditions, consuming mycoprotein could speed up the normal transit of foods from the small to the large intestine. This could, in turn, cause the fibre in mycoprotein to be fermented very rapidly in the large intestine, leading to symptoms of gastro-intestinal distress of the type reported by some consumers. The small numbers of consumers at risk from this type of gut response may have an imbalance in their normal gut bacteria, an unusual dietary intake of fibre (too low or too high) or may suffer from Irritable Bowel Syndrome.”
The conclusion here is: consult your GP for a proper diagnosis if you have suffered symptoms suspected to have been triggered by Quorn. It may not be an allergy.
This article has been reviewed by Dr Trevor Brown, Honorary Consultant in Paediatric Allergy, Ulster Hospital, Belfast; and Dr Michael Radcliffe, Consultant in Allergy Medicine, University College London Hospitals NHS Foundation Trust. We are not aware of any conflicts of interest with regard to their review of this article.
All the information we produce is evidence based or follows expert opinion and is checked by our clinical and research reviewers. If you wish to know the sources we used in producing any of our information products, please let us know, and we will gladly supply details.
All the information we produce is evidence based or follows expert opinion and is checked by our Clinical and research reviewers. If you wish to know the sources we used in producing any of our information products, please let us know, and we will gladly supply details.
Publication date: Nov 2017
Review date: Nov 2020