Though the terminology often gets confused, food sensitivities are different than food allergies. Food allergies are generated by the IgE branch of the immune system, and reactions will usually show up within minutes of ingesting the reactive food. Reactions can include an itchy rash, throat or tongue swelling, shortness of breath, vomiting, lightheaded, and low blood pressure; and can often be life threatening. Shellfish and nuts are the most common foods that result in an IgE food allergy.
Food sensitivities, on the other hand, are governed by different branches of the immune system: the IgA, IgM and IgG branches. These reactions may take as long as a few hours or even a few days to manifest, and may include acid reflux, bloating, irritable bowel syndrome, palpitations, joint pain, anxiety, tingling, or headaches.
The Most Common Offenders
The most common food sensitivities found in people with Chronic Disease are gluten, dairy, soy, grains (corn, in particular), nightshades (potatoes, tomatoes, and peppers), nuts, and seeds.
Gluten
Gluten is a protein found in barley, rye, and wheat. It’s a staple in the Western diet that’s found in most breads, cereals, and pastas, but can also be hidden in many other food products.
The most severe form of gluten response is seen in people with celiac disease. An estimated one percent of people (about three million worldwide) have celiac disease. Those with celiac disease must stay completely gluten free in both their diet and their lifestyle, or else they will have significant, life-affecting symptoms.
Reactions to gluten, many of which are also considered typical hypothyroid symptoms, include bloating, irritable bowel syndrome, acid reflux, stomach pains, brain fog, fatigue, hair loss, weight gain, cold intolerance, anxiety, palpitations, joint pain, carpal tunnel, allergies, and panic attacks.
My personal and clinical experience has shown that gluten sensitivity is one of the most significant triggers in Chronic Disease, and most people experience significant health improvements when they remove gluten from their diets. In fact, removing gluten can help reverse intestinal permeability (which is always a precursor to autoimmune disease) as well as reduce one’s thyroid antibody levels!
Dairy
Dairy is another common reactive food in people with Chronic Disease. Lactose intolerance, which involves a lack of enzymes that prevents the proper breakdown of the milk sugar lactose, is just one type of dairy reaction — but it is not the same as dairy sensitivity, which, like gluten sensitivity, is mediated by the IgG branch of the immune system. People with Chronic Disease are more likely than others to have sensitivities to the proteins found in dairy: casein and whey.
Cow’s milk contains proteins that are different than the proteins found in human milk. A person with intestinal permeability is likely to recognize these proteins as a foreign invader and make antibodies to the proteins.
As I mentioned, these antibodies are mediated by the IgG branch of the immune system and are known as a Type IV Delayed Hypersensitivity reaction.
Many people believe that non-cow milk options may be safer. However, goat’s milk and sheep’s milk proteins are very similar to cow’s milk proteins and have about a 60-75 percent cross-reactivity rate, meaning that 60-75 percent of people who are sensitive to cow’s milk casein will also react to goat and sheep’s milk casein. Once a person becomes sensitized to the casein protein, they will react to all forms of dairy, with the possible exception of camel milk.
The most common ways people react to dairy include gut reactions (bloating, diarrhea, and acid reflux), as well as lung reactions (coughing, asthma, sinusitis, post nasal drip, and mucus) and skin reactions (eczema, rashes, or acne).
For me, dairy was a greater reactive food than gluten. Eating even tiny amounts of dairy resulted in coughing, bloating, acid reflux, joint pains, and diarrhea. I’ve been dairy free for years now, and my food reactions are all but gone. However, a small amount of dairy will still trigger a cough for me.
Soy
The third food that those with Chronic Disease may be sensitive to is soy. Many gluten free products contain soy, which can be problematic for thyroid patients. It can block the activity of the TPO enzyme and worsen the autoimmune attack on the thyroid.
A soy sensitivity will often present as gut symptoms such as abdominal pain, loose stools, nausea or vomiting, while a significant number of people will also experience mental symptoms such as headaches, dizziness, brain fog, anxiety, depression, fatigue, and insomnia.
Soy can be hard to avoid, as it’s not only found in foods such as edamame beans, soy milk, tofu, tempeh, miso, and soy sauce, but also in many processed foods and even supplements. Ingredients to look out for include soy lecithin, bean curd, hydrolyzed soy protein, soybeans, edamame, natto, okara, yuba, tamari, olean, gum arabic, carob, and hydrolyzed vegetable protein.
Food Sensitivity Testing
When we eat the foods that our body is sensitive to, on a daily basis, it is very difficult to connect the foods with the symptoms we are having. For example, people who continue to drink milk multiple times a day might be tired, have joint pain, and feel bloated on a daily basis, but won’t be able to pinpoint the symptoms to a possible dairy sensitivity.
This is because every time we eat a problematic food, the body becomes depleted in its ability to protect itself, and the reactions become more chronic, making it more difficult to identify food sensitivities.
That is why I believe testing is so important.
There are a multitude of different food sensitivity tests out there, and none of them are perfect. Some will present with false positives; others, false negatives. You may have to try more than one approach to uncover all of the foods that are causing your symptoms, but there are two types of tests that I recommend most often.
Elimination Diet
The best place to start when trying to identify your own particular food sensitivities is with an elimination diet. The first step will be to remove gluten, dairy, soy, and other foods that you suspect you may be reactive to. These may include fruits and vegetables you’ve been eating all the time. Avoid these foods completely for at least two weeks. During this time, make note of your symptoms. Which have improved?

Which still remain?
After you have spent a period of weeks without the suspected food irritants, try slowly adding them back in one at a time, waiting several days between each food to notice if any of your symptoms return. Many people will notice an immediate reaction when they reintroduce a food they are sensitive to. If you experience this, take this as a very strong clue that you should avoid that food!
If, after removing gluten, dairy, soy and other foods you suspected were problematic, you are still experiencing symptoms of food reactivity, it might be time to dig a little deeper.
Test Kits
Some food sensitivities can be harder than others to pinpoint, and some people may need to see the numbers on paper before they are able to accept that they will need to give up a food they love in order to feel better. In those cases, I recommend food sensitivity testing through a lab. While most conventional medical professionals and insurance companies consider food sensitivity tests to be “experimental”, I can testify that as I “experimented” with removing the foods the tests found to be reactive for me, I felt dramatically better!
How Do I Eat This Way?
While it can be quite liberating to figure out which foods are problematic for you, and eliminating them can make you feel so much better than you have in years, you may find yourself asking, “How can I continue to eat this way, especially when the foods I am so sensitive to are so prevalent in our modern diets?”
Cook Your Meals at Home
When you’re avoiding certain foods, particularly foods like wheat and dairy that are so prevalent in our culture, the best strategy is to cook most of your meals at home. At least until you’ve mastered your diet and know where you can order specially prepared meals with safe ingredients in your area, it’s best to avoid eating out as much as possible.
If you feel like you may be missing out on social gatherings, try hosting a family dinner at home and incorporate some delicious new recipes. That way, you can control what food you are eating while still enjoying time with friends and family. If you’re heading to a gathering at someone else’s home or at a restaurant, try eating beforehand, or pack a bagged lunch and explain that you are on a special diet for a time. Most people will understand and be gracious about your health needs.
The good news is that there are so many delicious recipes that can inspire you to create some delicious home-cooked meals, while still avoiding the foods that cause reactions for you.
If you really don’t have time to cook, or just don’t like spending a lot of time in the kitchen, there are even some Paleo-friendly food services that allow you to customize your meal plans to your own food sensitivities. Paleo On the Go offers regular Paleo, ketogenic, and Autoimmune Paleo options, while Trifecta offers customizable Paleo and vegan options.
Adopt a Paleo-style Diet
Though being on a Paleo diet isn’t required for healing from Chronic Disease, and everyone’s diet is going to look a little bit different to suit their individual needs, I have found a Paleo-style diet to be helpful to a lot of people with thyroid issues. First, the Paleo diet eliminates the most common food sensitivities in Chronic Disease: gluten, soy, and oftentimes, dairy. Second, it places an emphasis on quality protein, fruits and vegetables — all of which are healing foods.
There are so many resources to be found on eating a Paleo-style diet, which makes it easy to incorporate into your daily life. For more information on what eating Paleo looks like, you can take a look at this article on Paleo diets, or this article that dives deeper into the Autoimmune Paleo diet.
Focus on Healing Foods
It can be easy to focus on the foods that you have to give up when you uncover your food sensitivities. I know first hand how hard it can be to give up some of your favorite foods. But, I’ve found it helps to place your focus on adding in nourishing foods that help your body to heal. When the food you are eating makes you feel great, it is much easier to give up the foods that made you feel so terrible!
Some of the foods I always recommend for people with Chronic Disease include green smoothies, bone broth, grass fed meats, fermented foods, gelatin, hot lemon water, beets, cruciferous vegetables, cilantro, fiber, green juices, berries, and turmeric. All of these foods have amazing healing qualities, and when you feel better, you will be encouraged to keep eating in a way that nurtures your body and keeps your Chronic Disease symptoms at bay.
Can I Ever Eat Those Foods Again?
The concern that most people have when they start to eliminate foods from their diet is that they will never again be able to enjoy the foods that they love. Some of us will even avoid doing any type of food sensitivity testing because we’d rather be ignorant to the news that we can no longer eat our beloved grilled cheese sandwiches and ice cream cones!
The good news is that, after a period of elimination and gut healing, there are many foods that you will be able to add back into your diet. Depending on how many foods you are sensitive to and how damaged your gut is when you begin eliminating foods, the amount of time you’ll need to wait before reintroducing those foods will vary. Everyone starts from a different place, and your own timeline may be different than the next person’s.
The turning point for me was when I began to incorporate nutrients, digestive enzymes and more healing foods like bone broth, green juices and green smoothies into my diet. I began to feel and look better, and began to tolerate more foods. Continuing to nourish my body, while treating gut infections and toxins, allowed me to eventually incorporate more and more foods back into my diet, and I’ve now been able to reintroduce most foods I was once sensitive to!
Before reintroducing foods to your diet, I suggest eliminating that food completely for a period of 3-6 months. One study from the Journal of Laboratory and Clinical Medicine looked at the half-lives of IgG antibodies in patients with immunodeficiencies and found that the total half life of IgG antibodies was 25.8 days. A half life refers to the amount of time required for a substance to be reduced to one-half of its previous level. Therefore, we can infer that it will take a period of several months for the antibodies to be fully eliminated from your body.
You will also want to make sure that your gut is healed by incorporating nourishing foods and addressing any gut infections that you may have. When you feel that your symptoms have abated, and you are ready to reintroduce some previously reactive foods, be sure to go slowly, introducing one food at a time to see how you feel.
What About Gluten and Dairy?
Though my body has healed to the point where I can tolerate all other foods I had previously eliminated, I still follow a gluten and dairy free diet.
In general, I believe that most people with Chronic Disease should stay gluten free. Though there are some people that seem to be able to add gluten back into their diets without incident, the majority of people will experience adverse reactions and seem to fare better on a gluten free diet.
Similarly, dairy seems to be problematic for most people with Chronic Disease, and I generally recommend that they continue to eliminate all dairy products from their diets. If you feel you’ve healed to a point where your gut can handle it, you can try adding in a small amount of dairy and note how you feel.
Again, each person is different and there is no “one-size-fits-all” diet that will heal everyone. You will need to experiment with what foods do and don’t work for you, and tailor your own diet to a way of eating that makes you feel great.
Next Steps
When my clients hear this information about food sensitivities, some are excited because they finally have a starting point from which to approach feeling better. Others feel overwhelmed, especially if they are dealing with debilitating fatigue, and wonder how they’re going to find the energy to incorporate a new diet into their lives. I’m here to tell you that the changes you make to your diet become easy to manage with a little time and practice, and the relief of symptoms you may experience will be more than worth it!
If you are feeling overwhelmed, I encourage you to take it slow. Try removing one food sensitivity at a time and give yourself time to adjust to the change. We are all different, with different sensitivities. What works for one person, may not work for the next. Stick with it and let your diet evolve with you — you are bound to find a way of eating that works for your lifestyle and makes you feel good.
References

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