February 16, 2012

Food Sensitivity vs. Food Allergy

Posted in Allergies, Asthma, Eczema, Digestion (or lack thereof) tagged , , , , , , , at 9:32 pm by Dr Michelle Torrance ND, LAc

Two scenarios commonly present in my office when it comes to food:

  1. A new patient who is suffering from a long standing illness or complaint comes to me because they are tired of standard prescriptions and therapies and want to try something more “natural”.
  2. A new or existing patient comes into my practice asking to have their “food allergies” tested. They have a suspicion that something that they are eating may be causing them to not feel well.

For both of these groups of patients, I probably will test them for some type of food intolerance – but I will be testing for sensitivity, not for allergy. There’s a big difference between the two!

Let’s Clarify

The primary difference between a food sensitivity and a food allergy is the part of the immune system that is involved. This does not take into account a mechanical problem with the digestion of food, such as a lack of an enzyme (ex. lactose intolerance or celiac’s), the over or under production and release of bile from the gall bladder, or a myriad of other digestive difficulties.

Food Allergy

An allergy is technically defined by the release of IgE antibodies in response to a food, pollen, dander or other irritant. The most common food reactions that most people think of is peanuts and shellfish. These are strong reactions, and not all food reactions will be like that. They have the potential to be that strong, but their primary defining trait is that they are quick. It is usually fairly easy to make a connection between eating a food and having some sort of negative reaction.

IgE is best tested by a skin prick test called a RAST.  I don’t do this test in my office, I usually refer out to an allergist for this.

Food Sensitivity

A food sensitivity is also an immune system reaction, but one that is defined by the release of IgG type antibodies. IgG antibodies are typically seen in reactions to viruses and bacteria. These reactions stay with the body a long time. By keeping the antibodies around and in production, the body protects itself from future injury by the same pathogen. The problem is when the “pathogen” is food. Food should never be considered the enemy, but sometimes the body does make a mistake and sensitizes to a food. The symptoms occur when we continue to eat the same food again and again. Eventually, the body doesn’t mount a big, acute reaction, it goes into a lower grade, chronic mode. As a result, the reactions are difficult to track and can be somewhat vague. Many people don’t realize what a problem their food choices are until they eliminate the foods and feel better as a result!

The way to test for these types of reactions is with an easy blood test. USBiotek and Genova Labs both provide excellent results and are a very good value, especially since many of these types of tests are considered out-of-pocket and aren’t always covered by insurance.