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Food Hypersensitivity - Food Allergy and Intolerance

In 2014, the European Food Safety Authority (EFSA) estimated that food allergies and intolerances occurred in approximately 3 % of adults and children. Though it is generally accepted that the incidence of food allergies and intolerance in industrialised nations appears to be increasing, determining precise numbers is difficult due to relatively mild symptoms in some cases and the unreliability of self-diagnosis.

The Food Hypersensitivity leaflet is designed to answer many of the questions people may have in regard to food allergies and intolerances, collectively known as food hypersensitivities.

  • Food is one of a number of allergy triggers (pollen, dust, animal dander, latex)
  • A food allergy differs from food intolerance in the type of reaction by the body
  • Symptoms and their onset can vary with the trigger and the individual’s sensitivity
  • People can experience hypersensitive responses to more than one type of food
  • Some foods can trigger both an allergic reaction and intolerance, e.g., milk, wheat
  • Processing a food, e.g., cooking may or may not alter its allergenicity
  • Avoidance is currently the only way of managing a food allergy or intolerance
  • Diagnosis of a food allergy or intolerance should involve medical consultation
  • Changes to your diet should only be undertaken in consultation with suitably qualified experts
  • EU food law identifies 14 specific food allergens that must be declared when they are used to produce or prepare foods
  • The requirement to declare/ label food allergens does not apply when they are present at low levels due to cross-contamination
  • Allergens must be declared in the list of ingredients of pre-packed foods, or elsewhere on the packaging where there is no ingredient list 
  • Allergen information for non-prepacked foods in Ireland must be provided in written format
  • Precautionary labels (‘may contain’) are voluntarily applied by food businesses

Food Hypersensitivity

More information about food hypersensitivity

  • Terminology

    The distinction between a food allergy and intolerance is not defined in legislation. Though interpretations can vary, experts in the field consider a food allergy to be a hypersensitive reaction to a food that is mediated by the immune system, particularly involving IgE antibodies, e.g. reactions to milk, peanut, soya, eggs, but also non IgE antibodies (gluten hypersensitivity or coeliac disease). An adverse reaction that does not involve the immune system directly is considered food intolerance, e.g. reactions to sulphites, lactose.

  • Symptoms

    Depending on the type of food and the amount consumed as well as the sensitivity of the individual, symptoms of an allergic reaction to food can appear within minutes to several hours after consuming a food. The reaction can be anything from mild irritation of the skin, mouth, gastrointestinal tract, etc., to anaphylactic shock which can be severe or even life threatening without medical intervention.

  • Anaphylaxis

    Anaphylaxis is a rapid and potentially life-threatening allergic reaction to various allergenic substances, including certain foods. People who are aware that they may be susceptible to anaphylactic reactions usually carry an adrenaline delivery device with them at all times. If a person is suspected of suffering from a severe allergic reaction, urgent medical attention is required.

  • Medical Diagnosis is important

    If a person believes that they have a food allergy or intolerance, the only long-term solution is to avoid that food. However, before any long-term solution is adopted, it is important to seek medical advice to determine whether any symptoms are actually related to the consumption of a particular food. A medical diagnosis of a suspected food allergy or intolerance can reduce the risk of unnecessary dietary restrictions, and also may reveal medical issues previously associated with food consumption.

  • Food Allergy and Intolerance in Childhood

    A food allergy or intolerance can appear early in a child’s life as they are exposed to new foods. Many childhood reactions to new foods are mild and resolve as the child gets older. However, where such reactions persist or get worse it may be prudent to seek medical advice.

  • Coeliac Disease

    Hypersensitivity to gluten (coeliac disease) is a genetically determined disorder that is estimated to affect 0.5-1 % of the Irish population and for which gluten avoidance is the only treatment. Gluten is a water-insoluble mixture of proteins that can damage the mucosa of the small intestines in people with the coeliac condition and is defined in EU legislation as “a protein fraction from wheat, rye, barley, oats or their crossbred varieties and derivatives thereof”. Foods containing no more than 20 mg/kg gluten can be labelled as ‘gluten-free’ while those processed specifically to reduce the gluten content and contain no more than 100 mg/kg, can be labelled as ‘very low gluten’. Coeliacs can avail of naturally-occurring gluten-free cereals such as rice, maize and sorghum. 

    Gluten is a water-insoluble mixture of proteins that can damage the mucosa of the small intestines in people with the coeliac condition and is defined in EU legislation as “a protein fraction from mwheat, rye, barley, oats or their crossbred varieties and derivatives thereof”.

    Ingredients containing gluten are specifically prohibited in the manufacture of infant formula and follow-on formula. In addition, processed cereal-based foods and baby foods intended for infants and young children under six months of age should indicate the presence or absence of gluten. 

    Foods labelled as ‘gluten-free’ or ‘very low gluten’ may be accompanied by the statements ‘suitable for people intolerant to gluten’ or ‘suitable for coeliacs’. ‘Gluten-free’ or ‘very low gluten’ foods may also be accompanied by the statements ‘specifically formulated for people intolerant to gluten’ or ‘specifically formulated for coeliacs’ if the food is specially produced, prepared and/or processed to reduce the gluten content or substitute the gluten-containing ingredients with other ingredients naturally free of gluten. 

  • Some foods can cause both an allergy and intolerance

    Certain foods can be responsible for both an allergic reaction and intolerance. For example, milk proteins can cause an allergic response in some people, while a reduced ability to metabolise lactose, the primary sugar in cow’s milk, is called lactose intolerance. 

    Certain derivatives of food allergens are exempt from food allergen labelling because the protein components known to elicit the allergic response have been removed during processing. 
  • Food Allergen Labelling

    Food allergens that require specific allergen labelling under the Food Information to Consumers (FIC) Regulation (EU) No 1169/2011:

    1. Cereals containing gluten, namely: wheat (such as spelt and khorasan wheat), rye, barley, oats or their hybridised strains, and products thereof, except:
      a) Wheat based glucose syrups including dextrose;
      b) Wheat based maltodextrins;
      c) Glucose syrups based on barley;
      d) Cereals used for making alcoholic distillates including ethyl alcohol of agricultural origin.
    2. Crustaceans and products thereof.
    3. Eggs and products thereof.
    4. Fish and products thereof, except:
      a) Fish gelatine used as a carrier for vitamin or carotenoid preparations;
      b) Fish gelatine or Isinglass used as fining agent in beer and wine.
    5. Peanuts and products thereof.
    6. Soybeans and products thereof, except:
      a) Fully refined soybean oil and fat;
      b) Natural mixed tocopherols (E306), natural D-alpha tocopherol, natural D-alpha tocopherol acetate, natural D-alpha tocopherol succinate from soybean sources;
      c) Vegetable oils derived phytosterols and phytosterol esters from soybean sources;
      d) Plant stanol ester produced from vegetable oil sterols from soybean sources.
    7. Milk and products thereof (including lactose), except:
      a) Whey used for making alcoholic distillates including ethyl alcohol of agricultural origin;
      b) Lacitol.
    8. Nuts, namely: almonds (Amygdallus communis L.), hazlenuts (Corylus avellana), walnuts (Juglans regia),cashews (Anacardium occidentale), pecan nuts (Carya illinoiesis (Wangenh.) K. Koch), Brazil nuts (Bertholettia excelsa) pistachio nuts (Pistacia vera), macadamia nuts or Queensland nuts (Macademia ternifolia) and products thereof, except for nuts used for making alcoholic distillates including ethyl alcohol of agricultural origin.
    9. Celery and products thereof.
    10. Mustard and products thereof.
    11. Sesame seeds and products thereof.
    12. Sulphur dioxide and sulphites at concentrations of more than 10 mg/kg or 10 mg/litre, expressed as SO 2.
    13. Lupin and products thereof.
    14. Molluscs and products thereof.
  • Cross-contamination with food allergens

    Consumers must be informed by the label when a food is produced with one or more of the specified 14 allergenic food ingredients. However, such labelling is not required where low levels of the allergenic ingredients are present as a result of cross-contamination. Where an undeclared food allergen is detected at low levels in a food, the FSAI may take proportionate action based on an assessment of the potential risk to public health.

  • Precautionary food allergen labels

    Food businesses sometimes use advisory labels such as ‘may contain…’ or ‘produced in a factory that uses…’ to alert vulnerable consumers that their product may inadvertently contain low levels of certain allergens. While such labelling is voluntary and can provide a valuable warning to consumers when prudently applied, they should not be used by food businesses as a substitute for good manufacturing practices (GMP) or HACCP strategies. The spurious use of precautionary labels can result in unnecessary dietary restrictions and possibly desensitise people with food allergies who may then take risks with those foods.

    Where an undeclared food allergen is detected at low levels in a food, the FSAI may take proportionate action based on an assessment of the potential risk to public health.

  • Provision of allergen information for non-prepacked (loose) foods

    Under the FIC Regulation (EU) No 1169/2011, allergen information must be provided for non-prepacked foods. This includes foods that are prepared by catering establishments, e.g., restaurants, takeaways and hotels, food and beverages presented and sold loose, e.g. unpackaged breads, cheeses, draught beer and cider, food packaged on site for direct sale to the final consumer, e.g., delicatessen, takeaway, and food provided by distance selling, e.g. ordered remotely for delivery. The FIC Regulation permits EU Member States to determine how allergen information for non-prepacked food is provided within their jurisdictions. In Ireland, this information must be provided in written format as set out in Statutory Instrument (S.I.) No. 489 of 2014. Details of how food businesses can comply with this requirement are set out in the FSAI information leaflet Allergen Information for non-Prepacked Food.

  • Monitoring the labelling of food allergens

    Prepacked food samples collected by environmental health officers are tested by the public analyst laboratories each year for the presence of certain food allergens. When clear breaches of the food allergen labelling legislation are detected, a food business may be asked to place additional labels on a product. However, depending on the potential risk, a product may be withdrawn or recalled and a notification sent to the EU rapid alert system for food and feed (RASFF). Even where labelling rules have not been breached by the presence of a food allergen, the FSAI may take action in the interests of consumer safety, based on an assessment of the potential risk to public health.

  • FSAI early warning system

    In 2009, the FSAI initiated an early warning system for people with food allergies or intolerances, or their guardians, and who have registered with the FSAI. This system enables real-time transfer via email and SMS text messaging of information about food allergy issues as the FSAI becomes aware of them. Registration for this resource can be made through the FSAI website at Subscribe To Email and SMS Alerts | Food Safety Authority of Ireland (

  • Make a complaint

    Consumers with a food allergy or intolerance are encouraged to contact the FSAI directly where they have had an adverse reaction to a prepacked food that they suspect may not be labelled appropriately, or to a food consumed in a catering establishment. Where possible, a sample of the suspect food should be submitted in order to establish the presence of particular allergenic ingredients.