Clients often come to me, stating that they can’t eat this or that. Often, people have cut foods from their diet because they think they might be allergic or have a sensitivity. So, first, what’s the difference between an allergy and a sensitivity? And second, how do you know if you have one?
An allergy is an immune-mediated response. That means that the particular food makes your body react as if it were being attacked, similar to if you came into contact with a virus or other germs. Your body mounts a response to “fight” the food that it has considered to be unsafe or foreign. This response can be a little rash, potential vomiting, an itchy tongue, or on the extreme end, what is known as anaphylaxis, which causes the airways to swell and become restricted, compromising breathing. This must be treated immediately and can be life-threatening. Even if the first time you have a food you only develop a rash, the next time, you could develop anaphylaxis. Unlike most sensitivities, allergies are also typically rapid in onset (within 2 hours of ingestion).
A sensitivity, on the other hand, is not life-threatening. Annoying, uncomfortable, even painful, sure, but won’t ever end in death. A sensitivity (or intolerance) is NOT immune mediated. This means that the body isn’t “attacking” anything, but simply doesn’t real like that particular food. Sometimes this is related to your digestive enzymes, like in lactose intolerance wherein the body responds badly to dairy because it doesn’t have enough of the lactase enzyme to properly breakdown the milk. Sometimes it’s related to poor gut health. If your intestinal tract has been chronically unhealthy due to stress, poor nutrition, etc, it may be hypersensitive and unable to process certain foods (gluten is a big one for this).
In either case, the best way to determine if you’re truly having trouble with a particular food, is an elimination diet. This should be done under the direction of a health care professional (like me!) to ensure it is done properly and yields the most accurate results. It involves removing all but a few foods from your diet for a period of time to help “re-set” the digestive system and the immune system, before re-introducing each food one at a time and watching closely for a reaction. In many cases, foods you thought you had trouble with will no longer be problematic, at least in moderate amounts, because the gut has been given a chance to heal and therefore can better digest. If you truly suspect an allergy, please be sure to do the reintroduction of foods in your doctor’s or an allergist’s office so that medical attention can be immediately paid should a reaction occur.
Removing foods, especially potentially nutritious ones like eggs, dairy, and nuts, simply on a hunch is never a good idea. Nutritionally, it may be difficult to fill those gaps, and for your own safety, it’s essential to know if you truly have an allergy so you can avoid all possible contact.
Aubrey Phelps MS RDN LDN