Food Allergy Versus Sensitivity

There are many things that can happen when you eat (or drink) something. In most normal cases, the food is digested to some degree and components are used by the body for building cells, creating energy or stored for later. This is an oversimplification, but you get the idea.

For those of us who have unpleasant reactions to food, the normal digestive processes are altered in some way. There are general categories of such reactions: allergies, sensitivities, intolerances, and a few others. Medically speaking, these reactions have distinct differences. As a common example, take lactose intolerance. When people with lactose intolerance ingest milk products, the milk sugar (lactose) is not broken down because those people lack sufficient lactase enzymes. The result is lactose fermenting in the intestines and producing gas, bloating, cramps and loose bowels. This is not an allergic reaction and not the same as a milk allergy.

What I’m going to focus on is the fine semantic line between food allergies versus food sensitivities, and whether there really is a difference.

What I have learned from multiple food allergy tests is that medical science typically identifies two types of allergic reactions to foods. These reactions are mediated by the presence of immunoglobulins in the blood. The immunoglobulins may be labelled IgE or IgG.

IgE reactions are those that cause the stereotypical allergic symptoms like sneezing, coughing, itching, rash, swelling, immediate vomiting, and possibly anaphylactic shock. These symptoms may appear within minutes to less than an hour after ingestion.

IgG reactions are typically delayed and produce more subtle symptoms like nausea, loose bowels, cramps, fever, body aches, headaches, fatigue, brain fog, skin rashes, and many others. These symptoms may not show up until hours or days after ingestion. This makes it somewhat harder to identify the offending food.

While there is not necessarily a hard and fast rule on this, many sources call IgE reactions true food allergies while calling IgG reactions food sensitivities.

In my specific case, I’ve never tested positive for, nor had any obvious reaction, indicating an IgE reaction to any food. On the other hand, my tests for IgG reactions show some sensitivity to almost everything! This is not entirely an accurate picture because I can safely eat some foods on the IgG reaction list while others that show no response have made me very sick. The main point I take away from the testing is that my body is simply really, really, really (to infinity) sensitive to nearly all foods. The only way to nail it down is with food challenges, previously discussed in an earlier blog.

Getting back to the semantics, the more recent doctors I’ve seen call my reactions food allergies, even if they are all IgG mediated. For ease of discussion with the general public, I call my condition “multiple food allergies.” It readily puts people on alert that eating things may make you very sick.

Not everyone views things this way though. I’ll give you an amusing anecdote. A few years ago, I had joined a very active and informative online forum for food allergies. After lurking a while and picking up some good tips, I finally formally introduced myself and talked about my condition. Well, I quickly got “flamed” (I think that’s the word). Other forum members were all over me for daring to join their forum discussions with what was not a “true food allergy.” Some of the people told me to go away and seek advice elsewhere. The only explanation I may have for their unwelcoming outbursts is that a lot of the forum members were moms of kids with life-threatening IgE food allergies. They want to protect the seriousness of their children’s concerns and not have them “diluted” by someone with less life-threatening IgG food sensitivities. Just…wow. I mean, food makes me sick. I thought all of us in that condition could hang together. I guess not.