This article will give a brief explanation of the differences between food allergy, intolerance and sensitivity. At the end of the article you will find a list of the most common symptoms so that you can see if you could be having any of these conditions.
Over the past ten years, major technological advances have been made, for instance within the field of immunology, or the science of the immune system. Today, we know much more about how the immune system works, and one result of improved technology is that scientists are now able to see what substances are liberated by the immune cells when they communicate with each other. Those substances are called cytokines and comprise substances such as interleukins, TNF-alfa, TNF-beta, interferon-gamma etc.
Despite the great technological advances, many aspects of the immune system remain uncovered. In addition, taxonomy – that is, naming – is in great dispute in relation to the different types of allergies, sensitivities and intolerances. When is it one of those conditions, when is it another? When doctors and other specialists cannot agree on defining the conditions, how should ordinary people be able to know their way around those terms?
The English term Adverse food reaction (negative reaction to foods) covers all of the above conditions. Many clinical studies indicate that all types of adverse food reactions may be the cause of a variety of diseases – such as depression, constant rhinitis, inflammatory conditions in the intestines, ADHD, epilepsy, hypertension and aching joints.
The classic type of allergy is what you call an IgE allergy. IgE is an antibody produced by your immune system in response to substances that are considered a threat. A typical example is allergy to peanuts. A person with a classic IgE allergy often has to eat just one single peanut to get a clear and often strong reaction that can be anything from a reddening around his or her mouth and a swollen tongue to anaphylactic shock – which is an immune reaction so strong that the body will go into a state of shock, and the person is in danger of dying. An IgE allergy will release large amounts of histamine in your body. One of the effects of histamine is clear fluid running from your eyes and nose – which is the case where allergy to airborne pollen is involved, also a classic IgE allergy. Another IgE allergy is rhinitis, also described as having an “all-year cold”. Of course you do not have a cold all year long, but a histamine-releasing immune reaction in your body produces a more or less constantly running nose. Instead of finding the underlying cause of the immune system provocation, the condition is often treated with medicine. An IgE allergy always produces a relatively quick reaction – often within a few minutes. Most people suffering from an IgE allergy therefore have no doubt about what substances they cannot tolerate so they can choose to avoid the specific substances.
In addition to the classic IgE allergy, terms such as sensitivity, hyper sensitivity and intolerance are used. There is no consensus as to what is covered by those terms, but one of the ways to look at it is as follows:
A sensitivity is also an adverse food reaction, but the symptoms are milder and less pronounced than with a definite food allergy. In addition, it may take one to four days for the symptoms to manifest themselves. It is consequently often difficult to know which food triggered the symptoms. In the case of sensitivities, reactions in your body will not involve the production of antibodies. The adverse reaction is triggered by other immune and inflammatory substances such as prostagladins, as seen in the case of food-induced IBS (irritable bowel syndrome) where the prostagladin production and consequently the colon inflammation are increased.
A food intolerance is an adverse reaction to a food caused not by a poorly functioning immune system, but often by nutritional deficiencies – for instance vitamin B6 deficiency – or by a poor function of the liver, resulting in a reduced ability to detoxify your body. Those deficiencies or reduced detoxification abilities cause an intolerance to histamine or tyramine that will result in bronchial contractions and hypertension as well as headaches, respectively.
Hyper sensitivity is a clearly defined term with four subgroups:
Type I: Classic IgE allergies such as hay fever and asthma.
Type II: Not relevant in relation to adverse food reactions.
Type III: High contents of antibodies and antigens in blood and tissue, often in the form of immune complexes. This type may cause autoimmune diseases, among other things.
Type IV: This type corresponds to the definition of a sensitivity as described above in this article. Certain immune system cells may attack an antigen – in this case the antigen from a food – and thus maintain an inflammation without producing antibodies.
The above terms are not applied consistently in literature, which can be very confusing to readers.
It often requires a dysfunctional immune system for an individual to react to a food that usually is not harmful. In by far the most cases, a normally functioning immune system will not react to the food you eat. By contrast, an off-balanced immune system will overreact more easily to food that should not and usually would not provoke a reaction.
On top of this and making it all the more confusing, food Q may provoke symptoms A and B in one individual and symptoms X and Y in another individual.
It is often mentioned that the main sources of adverse food reactions are foods such as cereals and milk products. That is probably due to a mixture of several factors, two of which are as follows:
- In relation to our genes, cereals and milk products are relatively new foods. In most cultures, people do not consume milk products at all after infancy and large parts of the world population lose their ability to break down milk sugar, or lactose, after infancy. Those people are described as lactose intolerant and include some Danish people as well. Lactose intolerance may be either hereditary or due to intestine inflammation that has damaged large parts of the places where milk sugar should be cleaved and absorbed.
In addition, in cereals as well as in milk there are elements that may be difficult for some people to break down. Those elements are gluten in cereals and lactose as well as lactoglobulins in milk. Today, milk is also heat-treated, and that destroys the natural contents of enzymes, among other things, which would otherwise have helped breaking down the milk.
- Moreover, the risk of reacting adversely to foods is greater with the foods you eat the most. Those foods are the ones that get in contact with your immune system most often, and for Danish people, often up to as much as 60-80% of their calorie intake comes from cereals and milk products. Try and write down how many cereals and milk products you consume on a daily basis!
Brief outline of this article:
- Some individuals react adversely when eating certain foods.
- The symptoms triggered by those adverse food reactions manifest themselves in different ways. Depending on whether allergy, sensitivity or intolerance is involved, symptoms will show within a few minutes or after several days.
- You can easily react adversely to food X in one way and to food Y in another way.
- Irrespective of whether allergy, intolerance or sensitivity is involved, many symptoms will disappear if you just avoid the foods that provoke an adverse reaction in your body. If, at the same time, you try to rebalance your immune system, you will experience a greater degree of physical well-being and an improved health condition without actually undergoing a treatment.
If you are familiar with one or more of the below symptoms, you may possibly react adversely to one or more foods:
- Alternating diarrhea and normal faeces
- Mood swings
- Mental confusion
See a doctor or a therapist about the possibility of an adverse food reaction being a contributory cause of your disease or health problems. Adverse food reactions often play a major part or even the principal part in the arising and/or maintenance of a wide range of conditions and diseases. If you are chronically ill or have a lifestyle-related disease, it will be relevant to find out if an adverse food reaction contributes to your illness due to an overreacting immune system.
Due to our stressful way of life in the West – and our often consequently dysfunctional intestine and immune systems – it is estimated that a very large percentage of Western populations reacts adversely to foods in one or more ways.
Today, there is an increased number of serious therapists and doctors who work considering the correlation between intolerances, allergies and sensitivities and their clients’ health. New laboratory tests have been developed in recent years, and your doctor or therapist can tell you about those tests.
You can also apply tools such as the elimination and reintroduction diet. This is a fine and inexpensive – yet a little complicated – way of finding out to what foods you react adversely.
In the next article about ”Food allergy, intolerance and sensitivity”, you will learn more about prick tests, the elimination and reintroduction diet, laboratory analyses and other tools.