Food allergy

Food hypersensitivity is the umbrella term for all hypersensitivity reactions to food. Food allergy, non-allergic food hypersensitivity (also called intolerance), and celiac disease (reactions to gluten) are all included. However, they are different conditions with different symptoms.

Complaint

The complaints that can occur with food hypersensitivity vary widely. Complaints occur:

in the gastrointestinal tract (itching in the mouth, nausea, abdominal pain, vomiting, diarrhea),
on the skin (itching, rash, eczema, fluid retention),
on the eyes (swollen, tearful, red),
in the airways (stuffy or runny nose, asthma, hoarseness, shortness of breath),
circulation and heart (anaphylactic shock which may result in death). This is only possible with an allergy.

Food allergy

With a food allergy, the symptoms are caused by an abnormal reaction of the immune system. The immune system produces specific antibodies against proteins found in food. These can be, for example, proteins from milk or nuts. Because the immune system reacts very specifically, the amount of allergen that can cause a reaction is very low.

The most serious reaction that can occur is anaphylactic shock. Various symptoms can occur, such as a sharply lowered blood pressure, swelling in the mouth or throat, breathing problems, loss of consciousness and sometimes even death. If the blood pressure drops quickly, cardiac arrest can occur. People can also suffocate after swelling of the throat, so that breathing is no longer possible. Often an allergic reaction occurs within minutes.

This reaction can only occur with a food allergy. In intolerance or celiac disease, this is not possible due to other reaction mechanisms.

Thresholds

In the case of a food allergy, the immune system produces specific antibodies (including IgE) against proteins found in food, such as certain proteins from cow's milk or nuts. Proteins that have the property to cause allergic reactions are also called allergens. Because the immune system reacts specifically, the amount of allergen that can cause a reaction is very low. The threshold values found - at which the allergen no longer provokes any reactions - vary greatly from person to person. Nevertheless, initiatives have been taken to establish general threshold values at which allergic reactions in allergic patients are unlikely. These thresholds are used in risk assessments of cross-contamination with allergens. Click here for more information on thresholds.

Allergenicity

Heating by boiling or frying does not affect the allergenicity in most cases, despite denaturing the protein. Click here for more information on the influence of process operations.

Prevalence

Researchers estimate that about 1 to 7% of people in Europe suffer from food allergies. It is more common among small children than among adults. There are indications that food allergies are becoming more common. Small children can "outgrow" an allergy, especially allergies to cow's milk and chicken egg. A peanut allergy, on the other hand, usually persists for life. Adults often do not get rid of their food allergies.

Some allergies are more common in certain geographic areas, probably due to differences in dietary patterns. For example, sesame allergy is common in the Middle East and celery allergy in the Mediterranean area, but less so in our regions.

In many cases people do not react to one substance but to several. Multiple allergies are common. Some combinations of allergies are more common; this phenomenon is called cross hypersensitivity. This phenomenon usually occurs with foods that belong to a closely related (botanical) family.

celiac disease

Celiac disease (pronounced seuliakia) is a reaction to gluten - the proteins from certain grains. IgE antibodies do not play a role here, but another part of the immune system. It's not an allergy, it's an autoimmune disease. There are also other complaints. An anaphylactic reaction does not occur when eating gluten. In patients with celiac disease, the intestinal surface is affected, resulting in poor absorption of nutrients. This disease is chronic in nature and manifests itself in various complaints such as abdominal pain, intestinal complaints, but also due to side effects due to nutrient deficiencies. By following a Gluten free diet the small intestinal mucosa can recover. This takes about a year. But every time gluten is eaten, new damage occurs.

Lactose intolerance

With food intolerance, the body also reacts to certain foods, but the immune system does not play a role. No antibodies are made by the body.
Lactose, a naturally occurring milk sugar, is an example of this. Lactose intolerance is caused by the inability to digest milk sugar. This is a metabolic problem. Lactose then becomes a food source for the intestinal bacteria, which convert it into gases. This causes cramps, flatulence and diarrhoea. People with lactose intolerance can often still tolerate a small amount of lactose.

More information
lactose-free products

Treatment and prevention of reactions

Although the symptoms of allergic reactions can be managed with medication, the only treatment for food sensitivities is to eliminate the substances that cause the allergic reactions. Depending on the substance(s) to which someone reacts, this is a difficult job that requires a great deal of knowledge about the composition and labeling of foodstuffs. In addition, all kinds of practical problems arise, such as explaining the situation to family, friends, but also, for example, to a playgroup or a restaurant. The availability of certain products is also difficult, going on holiday is difficult and people even become socially isolated.

It is therefore important that the label of products contains clear and complete allergen information. Both about the ingredients and possible cross-contamination with allergens. This information is also vital for non-prepackaged foods, such as in restaurants.
Allergen legislation is therefore in force in Europe.