Ask the Allergist: Food Allergies

Misunderstandings 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 will be quite helpful to the reader interested in this problem.

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. Am also having reactions at home intermittentently even though I am carefully watching food ingredients. It’s getting to the point where I no longer feel safe eating anything. 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.

RESPONSE:

There is no scientifically proven way to treat true food allergies besides avoidance. 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. Other people can have food intolerances, which cause less serious, non-allergic reactions to things such as a food additive or other ingredient (e.g. MSG syndrome or lactose intolerance which is caused by the inability to digest milk properly). 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.

Most of the time, when people believe they are allergic to a great number of foods, it turns out that dust mite is probably the biggest problem for allergy sufferers in South Florida. 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.

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), and understand that eczema may be worsened by foods. There are also well-described allergic syndromes such as milk-induced colitis in children. However, there are probably other food-induced allergic symdromes that have not been scientifically worked out.

Anyone who says that they have can give you allergy treatment for specific foods is, in my opinion, not practicing in ways that would be reported in a peer-reviewed journal like the New England Journal of Medicine. That is, they are practicing alternative or complementary medicine. Please note, that I am not trying to impart any opinion about the validity of alternative medicine. There have been some studies on allergy shots for treating IgE-mediated reactions to foods, but they have proven to be ineffective or to have unaccetable side effects.

When people have symptoms like you have, we treat the symptoms with medications, and try to avoid possible allergenic foods for that person. We mostly have great success with this approach. 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 approach for a prudent one in a person in your situation.

I hope this response is helpful.

Neil Gershman, M.D.