Food Allergy

About Food Allergy

About 1-5% of the total population have food allergies. You have a food allergy when your immune system is involved in the reaction to the food. Only your doctor can diagnose whether you have a food allergy as you may react to foods without being allergic.
More than 120 foods may cause food allergies. The foods that most commonly cause serious allergic reactions on a worldwide basis are: milk, egg, peanut, tree nuts followed by cereals (mainly wheat), soybeans, fish, and shellfish. Most allergic reactions among children are due to a limited number of foods, namely egg, peanut, milk, and tree nuts. Egg and milk allergy are often outgrown during the first years of life. Fruits, vegetables, tree nuts and peanuts are responsible for most allergic reactions to foods among adults.
People with pollen or latex allergy may often experience allergic symptoms when they eat certain fruits, vegetables or nuts. This cross-reactivity occurs because pollen and latex contain proteins that are similar to proteins in food, and the immune system may react to both. In fact, up to 70% of food allergies are related to pollen allergy. As a general rule, processing of a food does not alter the ability of the food to induce allergic symptoms. However, most people with a pollen allergy can better tolerate the cross-reacting foods when they have been cooked, baked, or roasted.
Symptoms of food allergies vary between different people, although a person will tend to have the same reactions each time the allergenic food is consumed. The symptoms of food allergies range from mild discomfort to severe, life-threatening reactions (anaphylaxis) that require immediate medical intervention.


Self-diagnosis of food allergy is notoriously unreliable, and failing to have a serious food allergy diagnosed could be potentially life threatening. Therefore, if you suspect that you have a food allergy you should seek specialist medical advice.

To diagnose food allergy the medical specialist will usually first talk with you about your symptoms, examine you for symptoms, and test if your immune system has created food-specific IgE antibodies. Skin prick testing and blood tests are the main tests used for this purpose. However, the presence of specific IgE does not necessarily mean that you will experience symptoms. Therefore, sometimes the only way to accurately diagnose a food allergy is to remove the suspected food from the diet to see if symptoms improve and if they do, give the suspect food in gradually increasing amounts to see if symptoms reappear. This is called a food challenge. Allergy specialists will always supervise the performance of challenge tests in a hospital or clinic, where the staff has established routines to safely manage any serious reactions.


When you are diagnosed with a food allergy, you need to remove all food products that cause reactions from the diet.
When you or others cook for you, it is important to avoid contamination of your food with the food that you do not tolerate. Contamination may happen through spilling, spatters, crumbs, not separating the diet food well, and dirty hands, plates, or silverware. It is therefore very important that you tell family, friends and different caterers about your allergy.
By law, the following allergenic foods or products made of these foods always will have to be listed when they are ingredients in a pre-packed food product in Europe:

Cereals containing gluten – i.e. wheat, rye, barley, oats and spelt
Crustaceans and Molluscs such as shrimp, lobster, and octopus
Milk, Eggs, Fish
Peanuts, Lupin, Soybeans
Nuts – i.e. Almond, Hazelnut, Walnut, Cashew, Pecan nut, Brazil nut, Pistachio nut, Macadamia nut and Queensland nut
Celery, Mustard, Sesame seeds
Sulphur dioxide and sulphites

Some foods have the label ‘May contain peanuts’ or ‘May contain milk’ etc. The food industry uses this label on their own initiative to warn allergic consumers of a possible contamination with an allergenic food. Different food producers use different criteria for using the ‘May contain’ label. Therefore the label represents different levels of risk.
It is often difficult to avoid certain foods and a risk remains that you, by accident, may eat a food which you do not tolerate. Mild symptoms may be treated with antihistamines. If you are at risk of severe allergic reactions, your medical specialist may advice you to carry the medicine adrenaline for emergency situations.


Food allergy has a significant impact on almost all aspects of daily life. Research has shown that:

  • Daily life is more disrupted in peanut allergic individuals than in individuals with a rheumatic disease.
  • Family activities were limited in families with food allergic children.
  • Female adolescents with food allergy feel more impaired health-wise and socially than female adolescents with other allergy-like conditions.