What Is It?
Food sensitivity (sometimes called intolerance) is a term used to indicate symptomatic responses when particular foods are eaten. Food sensitivities and intolerances tend to create more subtle symptoms than allergic responses, although over time, their impact on health and vitality can be dramatic.
In traditional medical circles, the lines between food allergy and food sensitivity can blur. For the sake of our discussion, we would like to make a clear distinction.
A “true” food allergy can potentially be life-threatening, eliciting an immune response that produces IgE antibodies. One common example we’ve all heard about is a child with a peanut allergy who must avoid even the tiniest amounts of peanuts in any form, or be overcome with disastrous symptoms. Thankfully, not all allergies evoke such an intense response, however IgE-mediated responses are generally observed almost immediately after the offending food is ingested.
The medical community recognizes that foods like milk, eggs and peanuts tend to trigger food allergies in children, and that peanuts, tree nuts, some fish and shellfish are common triggers in adults. The traditional doctor who doesn’t integrate nutrition into his practice tends to focus on these IgE-mediated issues when food-related symptoms are mentioned at all.
Food sensitivities are associated with IgG and sometimes IgA antibody production. The onset of symptoms in these cases may be delayed hours or even days, so associating an offending food with a subtle symptom can be elusive.
There are also some people who have reactions to foods that don’t involve the immune system and this is referred to as an intolerance. You may have heard of lactose intolerance. In this case, the person’s body doesn’t manufacture the enzyme lactase which is required to digest milk sugar, or lactose. This is entirely different from a milk sensitivity where an individual’s immune system reacts to the protein casein found in dairy.
What Causes It?
While some food sensitivities or intolerances can be caused by genetic factors, most commonly today alternative practitioners are observing IgG-mediated inflammatory reactions stimulated by different components of foods, most often proteins. It is interesting to note that even foods that we don’t normally think of as proteins do contain protein. Breads, fruits and vegetables all have a protein component. Commonly we hear of symptomatic reactions to gluten, eggs and milk however now you can see that these are not the only foods that could create issues. I’d like to make the point that a person can become sensitive to any food protein. Since food sensitivities commonly occur in conjunction with a digestive condition known as intestinal permeability, otherwise known as leaky gut, we need to understand that condition too.
A leaky gut can be the result of a high sugar diet, eating processed foods, taking antibiotics, stress of any kind, and/or an endless list of environmental toxins, more being discovered each day. The intestinal wall, a thin porous membrane that separates the intestine from the bloodstream, develops gaps and holes, allowing inappropriate food particles access to the blood stream.
Very often when a person is tested for food sensitivities, they are sad to find that that the foods they eat most often are the foods they are most sensitive to. That makes sense when you consider that, if they have a leaky gut, the foods they eat daily are crossing the intestinal barrier and can stimulate an immune response.
As the immune system reacts to the inappropriate substances in the bloodstream, over time systemic inflammation is created. Recent studies have shown that delayed, or hidden, responses that are created by IgG antibodies result in low-grade silent inflammation throughout the body. It’s important to realize that digestive discomfort is not always a symptom of this silent inflammation. I’m sure you’re beginning to see why the process of identifying a food trigger and then relating and healing the resultant issues can be so complex.
What Are the Signs and Symptoms?
As a person continues to ingest the offending food/s, the constant irritation damages first the gut and then the damage spreads systemically throughout the body.
This silent inflammation may demonstrate itself in myriad ways. Initial symptoms can range from headache, nausea, hyperactivity or fatigue, to bloating, dark circles under the eyes, even behavioral and mood disorders.
As a person’s health declines over time, they may receive diagnoses of any number of inflammatory auto-immune diseases. Recent research also indicates that this low-grade inflammation may directly block a person’s best attempts to lose weight, while contributing to insulin resistance, diabetes and many other chronic disease processes like cardiovascular issues.
I created a chart in my book Heart of Perfect Health that offers a simple overview of the system wide manifestations of silent inflammation.