What are food intolerances

Food intolerance is an abnormal reaction to certain foods that manifest in a number of different ways. Our test detects potential food intolerances in which there is an immune response that produces IgG antibodies.

The mechanism of food intolerance involves the production of antibody/antigen complexes, which are deposited in tissues, triggering the release of inflammatory chemicals that may lead to damage and inflammation in that particular tissue. For example: the gut, causing IBS symptoms; in the joints, causing arthritis; in the head, causing migraines

Physiological pathway of food Intolerance:

  • Partially digested foods pass between the gut cells into the blood
  • These foods or proteins are recognized as “foreign” and food specific IgG antibodies are produced in response
  • Antigen/antibody complexes form between the proteins and the IgG antibodies. The symptoms of food intolerance tend to be delayed because the formation of these complexes is gradual, not immediate.
  • The complexes may be deposited in tissues anywhere in the body, such as the joints, gut, skin, head, etc.
  • The complement system becomes activated in response to the foreign complexes,leading to a variety of symptoms.

The Link Between IgG Antibodies and Symptoms

Often people will consume a lot of their favorite foods, which may result in a higher level of IgG antibodies, although they may have no symptoms and this is normal. These antibodies will form antigen/antibody complexes against the partially digested food. An efficient immune system (i.e. macrophages) will clear these complexes before they are deposited in tissues.

When the immune system is compromised, the sequence of events is similar to that of a normal response, however there will be insufficient macrophages to clear away the complexes, and they will be deposited in the tissues, producing an inflammatory response leading to symptoms.

In the situation of increased gut permeability, the immune system is working efficiently, but the gut wall becomes more permeable, allowing an increase in the number of partially digested foods to enter the blood stream. The immune system becomes overloaded and not all of the complexes can be cleared, and the excesses are deposited in tissues causing symptoms. Factors that can lead to increased gut permeability include: stress, imbalanced gut flora, injury to the gut wall, low stomach acid and poor nutrient status.

Food Allergy is not the same as Food Intolerance

However the two are frequently confused A classical food allergy (such as peanut or shellfish allergy) is usually characterized by an immediate and often severe reaction of the immune system when exposed to a specific food. The reactions are related to the production of IgE antibodies by the immune system. Symptoms are usually associated with a classical ‘allergic reaction’ that can include: rashes, sneezing, skin irritation, diarrhea, vomiting, difficulty in breathing and anaphylactic shock. The most common instances of food allergy are to peanuts, tree nuts (almonds and brazils), eggs, milk, fish and shellfish. It is usually obvious which foods are responsible for a food allergy and these foods should be avoided even though they may be normal in the Health Food IgG Food Intolerance test.

Non Immune-Mediated Reactions

Other reactions that are often confused with food intolerances are those that that do not involve the immune system, that is, they are not related to the formation of antibodies. These non-immune-mediated reactions will not be detected by the Food Intolerance IgG Test. They can be caused by sensitivities to certain chemical/additives found in food, or may be due to an enzyme deficiency.

Lactose Intolerance is caused by a deficiency of lactase – an enzyme that breaks down lactose. Foods that contain lactose include: dairy products (milk, cheese, ice cream, etc.) Symptoms include bloating, diarrhea and flatulence. Tests used for diagnosis include lactose intolerance and the hydrogen breath test.

Histamine Intolerance is caused by an elevated histamine level due to a deficiency or inhibition of diamine oxidase, an enzyme found in the gut, that breaks down histamine. Foods high in histamine include: red wine, cheese and tuna fish. Symptoms include: migraines, dizziness, bowel/stomach problems, rhinitis, depression, irritation and reddening of the skin. Diagnosis is usually made by avoiding foods that contain histamine to see if symptoms improve. Confirmation is done by re-introduction of the foods into the diet.

Chemical Sensitivities occur when there is susceptibility or sensitivity to certain chemicals in foods, such as amines in chocolate and coffee, and food additives such as MSG. This can be confusing as the symptoms are very similar to food intolerances. A diary of foods eaten can help to identify if the cause of the symptoms are caused by a chemical sensitivity. If this is the case, the foods containing the chemical should eliminated from the diet for 2 – 3 months and your symptoms monitored for improvement.