Allergy or Sensitivity? I help you sort through the facts.
It seems like these days, everyone is allergic to everything…but are they truly allergic? It depends on your definition. Learn more about what a true allergy is, why we are reacting to food now more than ever and what to do about it.
The classic definition of Allergy refers to a process in which IgE immune cells are specifically activated to a food protein. The key here is that the protein is the allergenic component…so you can’t be allergic to lactose. The type of immune cell is also important because this type of immunity is very specific and the symptoms are too.
The nine most common food allergens in Canada are peanuts, tree nuts, sesame seeds, milk, eggs, soy, fish, sulphites and wheat. Symptoms can range from mild to life-threatening and include hives, rashes, wheezing, runny nose, trouble swallowing, dizziness and anaphylactic shock. Reactions are usually immediate and can be managed with an anti-histamine or for those with anaphylaxis, an Epi Pen.
In adults, there is another form of allergy called oral allergy syndrome that is related to environmental allergies. It occurs when the mouth becomes sensitized to pollens, which causes a cross-reaction to foods that have similar chemicals. For example, someone with a birch pollen allergy might cross-react to apples or cherries. Someone with a ragweed allergy might cross-react to zucchini or cantaloupe. Eating the food causes itching and swelling; however, cooking typically eliminates the reactivity of the food.
Intolerance differs from an allergy in that the body is not having an IgE-mediated reaction to a protein in a food. An intolerance usually occurs when a substance in a food cannot be broken down properly, leading to a reaction. Intolerance can be to a sugar (such as lactose), which creates digestive distress or a chemical such as histamine, which produces a response that looks like an allergy when in excess.
In addition, the word intolerance or sensitivity is also used to refer to an IgG4 delayed immune response to a food – this is the kind of intolerance that your naturopath usually checks you for, although there are some integrative docs doing it too. There is still a great deal of controversy around IgG4 intolerances – what causes it to occur, what it means to the body, can you heal the gut and reduce the intolerance – so there is still much we need to learn.
So how do you know?
If you think food is causing you to react, the first step is to go to your family doc to have anything more serious ruled out. They can screen you for celiac disease and might refer you on to an allergy specialist if they think it is classical allergy or a gut specialist if they suspect something like IBS. If nothing pans out on the medical route, now is the time to talk to a naturopath or dietitian skilled in food elimination and challenge to get to the bottom of which foods are causing you trouble. And remember, sometimes it isn’t the food itself but larger lifestyle challenges that cause the body to feel crummy. But discovering where the imbalances are takes commitment from you and your healthcare team to craft a road to amazing health.