The Difference Between Food Allergies and Sensitivities
What's the difference between a food allergy and food sensitivity (also known as an intolerance)? This is going to get a little technical, but here we go.
There are many different types of reactions that happen in your body. The reaction occurs when an immunoglobulin ( an immune protein that helps the body fight infection ) binds to an allergen.
There are five different types of immunoglobulins ( Ig ). They are labeled as such: IgG, IgM, IgE, IgA, IgD. These all have their own characteristics:
IgG is the most abundant in the body and can cross the placenta to give what's called passive immunity to a baby in-utero. It also is present long term and signifies past infection.
IgM is the largest of the immunoglobulins and is seen in active infections.
IgA molecules are specific for the linings of organs like the gut and even the lungs.
IgE is the one that is associated with outright allergy. That's the one that shows up with the skin scratch test and may let you know you need an Epipen for some really bad reactions that might make you die.
IgD is one of those that we don't deal with and isn't entirely understood at this point.
Food Allergy
As you can see the "allergy" is when your immune system mistakes a protein or other ingredient in food as a threat, is associated with one specific type of reaction, and the onset is immediate.
Symptoms of a food allergy:
Vomiting and/or stomach cramps
Hives
Shortness of breath
Wheezing
Repetitive cough
Shock or circulatory collapse
Tight, hoarse throat; trouble swallowing
Swelling of the tongue, affecting the ability to talk or breathe
Weak pulse
Pale or blue coloring of skin
Dizziness or feeling faint
Anaphylaxis (most severe and potentially deadly)
Now, just because IgE is present doesn't mean you need an Epipen. However, it does mean you should be avoiding it.
Food Sensitivity
Sensitivities (also known as intolerances) typically cover IgG and IgA. When these reactions take place it can take several hours or days to take hold.
Symptoms of a food sensitivity:
Abdominal (belly) pain
Diarrhea
Gas and bloating
Headaches or migraines
Heartburn
Nausea
Upset stomach
Theoretically, you can eat a food and have already eliminated it before the reaction takes place. This makes dietary journaling very difficult because we are always looking for the immediate response and that just may not be the case.
Main takeaway
The big difference between allergy and sensitivity is the severity of reaction and timing. Now, there are plenty more reactions in the sensitivity realm such as cytokine reactions and complement reactions. This gets a little farther down the rabbit hole, but can be extremely important in helping tough cases like autoimmunity and chronic illness.
If you're experiencing any of these symptoms and think you may have a food allergy or sensitivity and are interested in finding out what food(s) is causing this reaction, we can get you tested. Schedule an appointment today!