Misunderstandings and Misconceptions about Food Allergies
The following is a letter from a person suffering from what they believe might be allergies to food. Below is the letter and my response. I believe this question and response may be quite helpful to those suffering from symptoms they believe are caused by food allergies.
LETTER:
I was very excited to run across your web site, especially when I saw the mention of a food allergy specialist in your list of doctors. I am having very bad allergies with food and it is only getting worse. I can no longer eat at restaurants without having a reaction. I am also having reactions at home intermittently even though I am carefully watching food ingredients. It’s getting to the point where I no longer feel safe eating anything. I am currently taking shots for pollen and have been for two years, but it doesn’t appear to be helping.
I called up to find out more about your service and the receptionist told me you only test for food allergies, you don’t treat them. I was extremely disappointed to hear this.
If you do not treat food allergies, why do you list that you have a doctor with an expertise in them at your web site? This is very confusing advertising. Is there anything you do for food allergy sufferers besides test for what foods to avoid?
Thank you for your response.
A.P
RESPONSE:
First, it is very important to categorize food reactions. Bad reactions to food include both allergic and non-allergic reactions. True allergic reactions to a food are typically immediate, can be life threatening, and involve a specific immune system response. Skin or serum testing can measure this immune response (specific-IgE to foods).
Non-allergic reactions to foods, other than food poisoning, can be simply characterized as food intolerance. These do not involve the immune system at all, so any type of “allergy” testing is irrelevant. An example of this is milk/lactose intolerance, which can cause significant abdominal discomfort since the person doesn’t have an enzyme to break down the milk sugar. There are likely many other forms of intolerance which most people describe as “that food doesn’t agree with me.” I always tell patients that I don’t pretend to know everything about bad reactions to food, but “I don’t make stuff up.” Many patients come to our office with testing results that have no scientific or medical evidence to back up their use. I tell them that these tests, which they usually had to pay out of pocket for since insurance won’t cover them, are of no real medical value.
Sometimes, a “food allergy” turns out to be a gastrointestinal condition such as Irritable Bowel Syndrome. This is why I would recommend that you tell your Internist or Family Practice doctor about these symptoms, because it could represent another medical problem.
Until recently, there was no scientifically proven way to treat true food allergies other than avoidance and having emergency epinephrine auto-injectors on hand for severe allergic symptoms (current limited studies on food allergy treatment will be discussed below). Most people have allergies to one or a small number of foods (e.g. hives or wheezing after eating peanuts or shrimp), so this approach is usually successful.
An old allergist’s adage is that the longer the list of foods that the patient says they are allergic to, the more likely they allergic to no foods at all.
Most of the time, when people believe they are allergic to a great number of foods, it turns out that their symptoms or rashes are unrelated to food. If you are having frequent random “reactions,” you might assume it must have been the last thing you ate. This is a logical thought to have if the symptoms resemble a true allergic reaction. We have people coming in all the time with chronic hives, and 80-95% of the time they have no food allergies. I believe you are suffering a great deal, but it may not be allergies at all.
The main point being, if you are always itchy, you are always going to want to blame it on something you are eating. Think about it – during an average day, you eat or drink something every few hours. It is just human nature to blame the rashes on food. However, many people have itchy rashes due to a skin condition, especially atopic dermatitis (eczema). Incidentally, an allergist or dermatologist can prescribe anti-inflammatory creams that can successfully treat itchy rashes.
I should also mention that medical science doesn’t have a very good understanding of food allergy in general. We understand IgE-mediated allergy very well (e.g. immediate hives after eating walnuts). We have also come to understand that food allergies are not an important cause of atopic dermatitis, even though many children with this condition have positive food tests. There are also well-described allergic syndromes such as milk-induced colitis in children. However, there are probably other food-induced allergic syndromes that have not been scientifically worked out.
I mentioned above that there are some studies going on regarding the treatment of food allergy. These limited studies are looking at desensitizing subjects with only IgE-mediated reactions to foods, reactions that include hives or wheezing immediately after food ingestion. Most of these studies are on egg, milk, and peanut. There are a handful of private allergy doctors across the country that are doing oral desensitization in their office, but the majority of allergists are waiting for approved treatment kits to be approved by the FDA.
Other than the specific desensitization protocols I mentioned above, you may find practitioners of various sorts stating that they will treat your food allergy. Many of these people are practicing alternative or complementary medicine that is not scientifically validated. I do believe alternative and complementary medicine have a place, but a prospective patient should go in with their eyes open.
When people have symptoms as you have, we typically do some testing to make sure we aren’t missing a true food allergy. Then, we treat the symptoms with medications and have the patients keep a food diary to see which foods might be causing non-allergic reactions. We typically have great success with this approach, with the patient having to avoid few, if any, foods and having a good healthy diet.
We as Allergy/Immunolgists have all had specialized training in food allergies, so we are “food allergy specialists.” Doctors in our specialty generally stick to conventional, scientific, evidence-based medicine. We feel this is a prudent approach for a person in your situation.
I hope this response is helpful.
Neil Gershman, M.D.
Dr. Neil Gershman is a graduate of the University of Miami School of Medicine. He did his Internal Medicine training at Montefiore Medical Center of the Albert Einstein College of Medicine and his Pediatric Allergy/Immunology and Adult Allergy/Immunology fellowship at the University of California, San Francisco. During the fellowship he concentrated on asthma research involving inhaled steroids and other anti-asthma drugs. Dr. Gershman is certified by the American Board of Allergy & Immunology. He currently resides on the Advisory Board of the regional chapter of the American Lung Association. He is a Fellow of both the American Academy of Allergy and Immunology as well as the American College of Allergy and Immunology.
Dr. Gershman is a past President of the Florida, Allergy, Asthma and Immunology Society.
