Food sensitivities are pervasive in our culture these days. Restaurant menus often include gluten- or dairy-free options to accommodate patrons with some of the more common food restrictions. This unfortunately leads to an eye-roll by many who are not familiar with the nature of food allergies and sensitivities. If you take a minute to read the science behind food sensitivity, however, you will see that negative reaction to food is a real and common phenomenon. According to some estimates, 60% of the population may suffer from undetected food sensitivities and these sensitivities can lead to a multitude of unexpected health issues. In better understanding what food sensitivities are, we are able to empathize with those who have them and perhaps look at our own diet and consider whether we, too, may be part of that statistic.
First of all, let’s discuss the difference between food allergy and sensitivity. A food allergy is a type 1 hypersensitivity immune response of which symptoms arise within minutes to hours following exposure to an allergenic food. Symptoms range in severity from mild (hives) to severe (anaphylaxis). Peanut allergy is an example. Allergenic foods are avoided in individuals because exposure can be at best uncomfortable and at worst life-threatening. Not all negative reactions to food, however, result in a classic allergic response. There are other categories used to classify adverse food reactions, one being that of food sensitivity. Food sensitivities can result in immune reactions (other than type 1 hypersensitivity) or may not be immune-mediated at all. Either way, food sensitivity reactions are typically slower to develop, taking hours to days to appear. Although not immediately life-threatening as can be the case with food allergy, food sensitivity can lead to a myriad of symptoms and clinical syndromes also ranging from mild to severe. Food sensitivity has been implicated in medical conditions such as irritable bowel syndrome, chronic sinusitis, migraines, depression, obesity, and autoimmune disease. The list is surprisingly long of conditions where food sensitivity may play a causative or exacerbating role.
Food allergies can usually be identified by bloodwork or skin prick testing. Food sensitivities, on the other hand, are more challenging to diagnose. There is no definitive blood test for food sensitivities and the available testing is controversial. I have found food sensitivity testing to be useful in particular scenarios, using the results not as definitive proof but rather as a tool to guide the investigation. Just because a person is not allergic to a food by the standard definition does not mean that they tolerate it well. If you suffer from a chronic condition that has been linked to food sensitivity, it would be worth investigating the potential association of your condition with the food you eat.
Because symptoms of food sensitivity take longer to develop, the culprit food/s can be difficult to identify. Imagine if you had a piece of cheese with breakfast yesterday morning and started having stomach pain today. How would you know if your stomach pain is related to the cheese or one of the 20+ other foods, spices, and additives you consumed in the past 24 hours? Some of the most common offenders for food sensitivity are sugar, dairy, wheat, soy, corn, eggs, citrus, and food additives. I have also seen the culprit in food sensitivity be something as seemingly innocent as a spice.
The best and most accurate way of determining food sensitivity is through an Elimination Diet. An Elimination Diet is an eating plan in which potentially problematic foods are eliminated from the diet for a specified amount of time and then reintroduced to determine if they cause negative effects. The elimination period is typically 21 days, during which time the food/s must be completely excluded. Because of the nature of these delayed immune responses, if the food is not completely eliminated for the specified period of time the results will be inaccurate. An elimination diet may exclude one food or many, based on the person and their goals. It is not uncommon for symptoms to worsen after starting an Elimination Diet before they improve. After the elimination period, each excluded food is challenged in a careful fashion, usually every 3-4 days per food, and symptoms monitored. If a problem food is identified, it is again eliminated and reintroduced at a later time. The Elimination Diet is not appropriate for people with severe food allergies, as challenging an allergenic food can result in dire consequences, such as anaphylaxis. However, if food sensitivity is a possibility, the Elimination Diet is an excellent way to investigate.
I use Elimination Diets for both diagnosis and treatment. It is one of the best tools I have in my integrative practice for starting a health investigation. Getting to the bottom of a food sensitivity can be a challenge, the answers are not always straightforward, and the process requires time and commitment. However, the reward will more than justify the time and effort. Often, this exercise alone is what is needed to get a person feeling better.