Let’s start with the word allergy. When people hear the words food allergy, some people think that they have a pretty good idea about what that means.
The first thought is often of anaphylaxis, which is swelling of the tongue or throat that could be life threatening. This is typically the assumption when we are discussing, for example, a peanut allergy.
Of course there are other foods that can trigger an anaphylactic reaction, such as other nuts, shellfish, strawberries, milk, and eggs. And just about any other food has the potential to trigger an anaphylactic reaction. But thankfully, anaphylactic reactions to most foods are relatively rare, so you don’t often hear about them.
Based on this information, you might assume that food allergies are always severe or life-threatening. But then you might remember that sometimes a food allergy merely causes hives. Hives are irritating, itchy, and unsightly, but they aren’t life-threatening. Lots of different foods can cause hives, including peanuts. So a food allergy doesn’t have to be life-threatening, nor does an allergy to one particular food, such as peanuts, lead to the same symptoms in everyone.
Confused yet? If not, we’re just getting started.
Other people believe that food allergies are defined by the mechanism underlying the reaction. Different parts of the immune system can cause inflammation and thus symptoms. With most food allergies, it is assumed that an IgE antibody reaction is involved. IgE antibodies are produced by the immune system and can lead to histamine release, which causes inflammation.
However, just because you have elevated IgE antibodies to a food does not mean that you will automatically have an obvious allergic reaction. Also, elevated IgE antibodies do not represent the only pathway that causes anaphylaxis or hives.
So what is an allergy? It depends on who’s doing the talking and on the context of the story. Take, for example, your typical newspaper or magazine article. When they use the word allergy, they are defining it by symptoms.
This is the same thing that your traditional allergist does.
Allergists define food allergy by a very limited set of symptoms that they can see with their own eyes.
These symptoms are: anaphylaxis, hives, asthma, and eczema. That’s it. If you don’t have one of those four symptoms, then you don’t have a food allergy. Period. End of story. At least according to people who’ve defined allergy by only four symptoms.
Allergists don’t define allergies by some complex scientific method. They don’t diagnose food allergies based on the presence of IgE antibodies, unless they also go hand in hand with one or more of those symptoms. If you have IgE antibodies to a food, but the allergist doesn’t see you suffering from anaphylaxis, hives, asthma, or eczema, then they won’t diagnose a food allergy.
When you read a story that states that “only approximately 2% of the population has a food allergy,” they are referring only to people who have one or more of those four symptoms. Unfortunately, the story usually neglects to tell you that. Then the article may go on to state that all of this talk (by the public) about lots of people having allergies is nonsense and that food allergies are being over diagnosed.
Is that true?
Well, only if you are working with a traditional allergist or reading an article in a popular newspaper or magazine. Once we open our eyes to all of the hundreds of other symptoms that you can get from a food allergy, then you start to see the bigger picture.