Wednesday, May 4, 2011

The Difference Between a Food Allergy & a Food Sensitivity

There seems to be a lot of confusion surrounding how a food allergy is different from a food sensitivity, so here is the abridged version. In both, our body's immune system mounts an attack on a foreign protein; however, the difference lies in the type of antibodies initiated, the time frame in which symptoms arise, and in some cases, the types of symptoms experienced.

A food allergy initiates the aggressive immunoglobulin-E (IgE) response within minutes or seconds of exposure to the offending protein. Symptoms can include rashes, hives, nausea, stomach pain, diarrhea, itchy skin, eczema, shortness of breath, chest pain, swelling of the airways, and anaphylaxis (1). Think peanut allergy and EpiPen.

A food sensitivity initiates the less aggressive immunoglobulin-G (IgG) which often has a delayed response time of hours or days. Due to the delay, it can be very difficult to determine what the offending food is. Symptoms include fatigue, gastrointestinal problems, skin rashes, dark circles under the eyes, muscle or joint aches, reoccurring ear infections, headaches, diarrhea, sleep disorders, runny nose, congestion, irritability, irrational behavior, anxiety and more. The list is long and includes skin, respiratory, intestinal and/or behavioral changes (2, 3).
A snap shot of my IgG food sensitivity blood work results for dairy.

Both IgE and IgG antibodies contribute to inflammatory responses throughout the body and so technically, they are both allergies. However, the key difference between the two is the body's reaction time to the allergen and symptoms experienced. While exposure to IgG allergens can cause long term health consequences, exposure to an IgE allergen can be deadly immediately (3).

I tend to lump food sensitivities under the banner of food allergies because I find that the term food sensitivity doesn't seem to elicit a serious enough reaction. Unfortunately, many people don't 'believe in' or 'buy into' food sensitivities as being a real allergy. Doctors often down play their existence or the need for testing. Since many of the symptoms are not what we've come to recognize as true allergy symptoms and because they are often delayed, they are passed off as being the result of something else - even an overactive imagination or paranoia.

Living with food sensitivities is serious business though, as anyone who suffers from them - or lives with someone who suffers from them - can tell you. When exposure to an allergen happens multiple times a day, potentially every day, it puts the body in a state of constant inflammation. A stressed immune system has difficulty dealing with colds, flus and other infections. It puts the body at risk for developing more serious conditions down the road, such as auto-immune diseases, heart disease, cancer and infertility, among others. After the birth of our son, my digestive system was a mess. I suspected that dairy was bothering me, but I had no idea to what extent until I sought an IgG blood test.

If you think you have a food sensitivity - and I believe that due to the lack of information on the subject, more of us do than we realize - there are options. Find a doctor that will take your concerns seriously and is well informed about food allergies and food sensitivities. We went the Naturopathic Doctor route, and ordered a take home IgG blood test through Rocky Mountain Analytical. Another option is to do an elimination diet, where the most common allergens are removed from the diet and then gradually reintroduced in order to determine which ones elicit a reaction. The elimination diet is considered to provide the most reliable results.

Most importantly, listen to your own body. It's not normal to experience the above symptoms - if you are, your body is trying to tell you something! Get tested.

Sources:
(1) http://www.allergykids.com/uncategorized/food-allergies-food-sensitivities-what-you-need-to-know/
(2) http://www.allergykids.com/uncategorized/food-allergies-food-sensitivities-what-you-need-to-know/
(3) http://www.askdrsears.com/html/4/t041800.asp#T041803

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