You are currently viewing Know The Difference Between Food Allergies, Sensitivities, and Intolerances

Know The Difference Between Food Allergies, Sensitivities, and Intolerances

As the holiday season is approaching and people are preparing for unforgettable celebrations and indulgent meals in the warmth of their homes, this is the perfect time to revisit some of the food related issues that you should be mindful of this season. These are food allergies, food sensitivities and food intolerance. Telling them apart might be extremely hard, but it’s crucial, as they require different treatments and behavioral changes. In this blog post I will try to guide you through the labyrinth of food-induced problems and help you find a solution that works for you. So, let’s get started. 

Are humans becoming more allergic to food? Is food becoming more toxic for humans? These types of questions have been capturing the popular tabloids in the past decade. Gathering accurate data is complicated. Many people tend to self-diagnose these issues and while they might truly experience food-related problems, they tend to label everything as “a food allergy”, which might not be the case. 

Some say that allergies and food issues are not necessary on the rise. It’s just that people have become more aware of the effect of food on our bodies and get diagnosed more often, driving up the numbers. There are also interesting theories suggesting that defeating various types of worms left our immune systems “bored and unemployed”, as one of the major threats was no longer an issue. As a result, the immune system had to find something else to fight and started responding to food products like nuts and dairy. 

Of course, the idea that we are over-protecting our children is also prominent, saying that keeping the environment too sterile actually debilitates immune response, leaving us more vulnerable. 

One way or another, it’s clear that food-related issues like food allergies, sensitivities and intolerance are here and they make our lives miserable. Knowing how they are different from each other and how to diagnose and treat them is more important than ever. 


Food allergies, sensitivities, and intolerances are terms used to describe different reactions that individuals may have to certain foods. While they all involve adverse reactions to food, they vary in terms of their mechanisms, symptoms, and severity. 

  • Food allergy involves the immune system, which gets triggered when your body mistakenly identifies a food protein as harmful and starts reacting to that by producing Immunoglobulin E (IgE) antibodies. The release of histamine is what leads to the symptoms of allergic reaction. All of this happens very quickly, within minutes from ingesting the allergenic food.
  • Food sensitivity does not always trigger immune responses and the reaction to food is usually less severe. When it causes an immune response, it is caused by Immunoglobulin G (IgG), which causes a more delayed response compared to IgE which was present in case of food allergies. The pathways through which non-immune sensitivities emerge are not well understood, however, food sensitivity symptoms appear over time. It is often triggered by repeated exposure to certain foods, which causes chronic inflammation and manifests itself in food sensitivities. So, you might be suffering from something you consumed several days ago! 


Sick lady

This delayed reaction complicates the matters a lot, because people don’t tend to associate symptoms with something they ate over previous days. So, they understandably blame the symptoms on other things and might continue consuming these foods, further complicating the matters. 

  • Food intolerance does not involve the immune system and release of IgEs and IgGs at all. It is fully linked to the body’s inability to digest certain food components, often due to enzyme absence or deficiencies. The most common example is lactose intolerance, which emerges because some people lack enzymes needed to digest lactose. 
  • Histamine intolerance is another condition that is related to immune response. For example, in the case of food allergies, histamine is one of the chemicals that is released to induce symptoms like swelling and itching. Histamine is often misunderstood, but their role in a healthy body is extremely important. For example, it facilitates immune reaction by dilating blood vessels, allowing white blood cells to reach the infected area of our body sooner. Once the allergic reaction is over, our body naturally breaks down histamines, so that the immune system can cool down and get back to normal. However, if the body fails to regulate histamine levels, people develop histamine intolerance, which can cause a number of symptoms that are commonly associated with allergies. 

While these conditions are related and you might be experiencing a combination of problems, each one requires a different set of diagnostic tests and treatment approaches. Firstly, it’s important to establish the overall level of inflammation in your body using inflammation assessment. It analyzes blood samples and can help rule out or detect various health conditions. 

For food allergies the go to test is IgE test which measures the level of IgE when in reaction to different allergens. IgG, IgM and IgA testing can be used for food sensitivities. These are the basic tests that give the first impression about the body’s response to different foods. 

However, testing for food sensitivities could be a complex process, as there are extremely many compounds and food types to test. Further, there is no ‘perfect’ food sensitivity test currently available that always gets it right.  There are a number of variables that can affect your food sensitivity results, thus always good to work with a practitioner that can help navigate you through these waters. Also, you might be sensitive to something that is not commonly tested or it is possible that you are getting false results, which is less likely, but not impossible. In this case, the best you can do is try an elimination diet. 

Elimination Diet

Elimination diet is a systematic approach that removes specific foods from your diet for a certain period of time to determine the key foods that cause negative symptoms and reactions. The primary goal of elimination diet is to identify and manage food sensitivities, allergies or intolerances. 

The first stage of the elimination diet is making a plan. During this phase you need to identify specific foods which could be causing negative symptoms and you eliminate them for a few weeks to clean your body from these potential allergens. 

Next, you start reintroducing individual foods one at a time at regular intervals. In this process, you carefully observe your body and monitor the reactions. Things to pay attention to include changes in energy levels, digestive health, skin conditions, mood, etc. Other symptoms include bloating, gas, abdominal pain, diarrhea and constipation, respiratory symptoms like nasal congestion, headache or migraine, sleep patterns, etc. 

Of course, conducting this “experiment” takes time and can last somewhere between 6 to 8 weeks depending on the list of the foods you decide to test, however, if conducted properly, the benefits will be worth it. Identifying food sensitivities alone will help you avoid foods that have adverse effects on your body. This process can also help you manage chronic conditions, improve digestive health and enhance overall well-being.

What’s important is that elimination diet can be adjusted to test not only for food sensitivities, but also for histamine intolerance, during which you remove high-histamine foods and introduce histamine reducing foods (you can find the list here); and for testing food intolerance to test which compounds might be messing with your digestive system. 

While the process of elimination diet seems intuitive and easy to implement, it is advisable to plan it together with your health professional to establish the type of elimination diet, as well the list of foods for which to test. They will also tell you how to reintroduce certain foods, how to time these changes in diet and how to track the changes. 

Elimination diet can unfold a lot of useful information and teach you many things about your body. If this is something you want to consider, feel free to schedule a consultation with a health professional who will guide you through the process.

Also, if you want to read more about food sensitivities in children, histamine intolerance and diagnosing in women, food diaries for tracking your reactions and other food-related problems, I invite you to visit our website. We at the Dempster Clinic – Center for Functional Medicine actively try to educate our patients about food related issues that might at the center of their symptoms. 

If you think that you might be suffering from food-related problems but are not sure where to start, feel free to contact us today. Here at The Dempster Clinic, you can sign up for a complimentary Discovery Session for you. This 15-minute consultation with me could be the start of getting your health on track and helping you feel better than ever.

Let’s address those food related symptoms and enjoy a happier and healthier life. Happy Holidays!

In Health,

Dr. John Dempster, ND