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Food Intolerances >> The Complete Guide for Healing Celiacs

For me, avoiding foods I’m intolerant to is the difference between a happy and productive day and binge watching Netflix on the couch. Finding my food intolerances and learning how to avoid them is one of the best things I did for my health, happiness, and healing.

how to find food intolerances

Many of you have written to me asking how I found my food intolerances. I want to help you take the same action that increased my energy and happiness exponentially!

In this post, you’ll find:

  • Symptoms of Food Intolerance
  • Common Food Intolerances + Sensitivities
  • How to Find Your Food Intolerances

Disclaimer: Please know that I am not a medical professional, nor do I intend to take the place of one. I found doctor’s visits to be of little help in this area, so I am sharing my experience finding the foods that do not sit well with my body and symptoms reported by me and others within the VgF community. It is always a good idea to get help from a trusted medical professional when experiencing prolonged digestive distress or making dietary changes.

Symptoms of Food Intolerances:

Common Food Intolerances Symptoms:

Digestive symptoms such as diarrhea, constipation, gas, bloating, stomach pain or discomfort, acid reflux, nausea, and disrupted hunger & fulness cues are all common symptoms of food intolerances.

Other Food Intolerances Symptoms:

Neurological symptoms such as brain fog, migraines, and headaches as well as skin rashes can also indicate food intolerances.

My experience:

One of the biggest signs of food intolerances for me is that I can’t read hunger and fullness cues. I could keep eating forever, or forget to eat a meal. All while feeling bloated, crabby, exhausted, and experiencing acid reflux.

Common food intolerances + Sensitivities

The terms intolerance and sensitivity are often used interchangeably. While there are two different types of food intolerances/sensitivities, the process for finding them is mostly the same.


Found in wheat, barley, and rye, gluten can cause a multitude of health issues. For people with celiac disease, gluten is the trigger of autoimmune symptoms (your immune system attacks healthy cells in your body).

Even without celiac disease, gluten can be a difficult protein for bodies to break down and process. This can lead to symptoms of food intolerance. It is also a common sensitivity and is theorized to have negative impacts on other conditions such as ADHD.

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This category includes milk, yogurt, cheese, cream, and ice cream. Dairy can be a tricky intolerance to find because there are 3 different components that could cause your body distress.


The sugar in milk, known as lactose, requires enzymes produced by the lining of your small intestine to digest. It is also an enzyme that some bodies stop producing with age.

People with Celiac disease or Crohn’s disease can have trouble digesting lactose due to damage to the small intestine.


Casein is most commonly found in cheese, however it is sometimes used as a food additive.

Due to similarities in the protein structure of casein and gluten, people unable to eat gluten sometimes cannot have casein as well. This is called a “cross-reactive” protein.


Found most predominantly in soft cheeses, milk, yogurt, and protein powders. Whey protein has some medical documentation relating it to symptoms of rheumatoid arthritis. It can also be difficult to digest.


Soy products include soybeans, edamame, soy sauce, miso, and vegan dairy alternatives. Although recognized as a common food intolerance, reasons for the intolerances are less concrete. Some studies suggest it disrupts normal hormone function while others note that soy can cause digestive symptoms. 


In addition to corn in its natural form, corn is often used as a starch for a variety of packaged foods. This is particularly true in the USA where corn grows in abundance.

Some people struggle with corn that is genetically modified (GMO), and find they can eat non-GMO corn products without symptoms.


Caffeine is found naturally in chocolate, some teas, and coffee. Sensitivity to caffeine often can take the form of ‘the jitters’ and anxiety in addition to digestive upset.

Caffeine Food Intolerances


Nightshades are more likely to cause problems for individuals with a compromised gut due to IBD (Inflammatory Bowel Disease), Celiac disease, or acute IBS (Irritable Bowel Syndrome). They contain potentially irritating chemical compounds that are linked to inflammation.

Foods in the Nightshade category include white potatoes (not sweet potatoes), bell peppers, hot peppers, tomatoes, and eggplant.


Some people with IBS or newly diagnosed Celiac disease feel relief on a low FODMAP diet. This means eliminating foods high in FODMAPs, which stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. Or in more understandable terms, foods with complex carbohydrate and sugar chains. These include wheat, some fruits and vegetables, and legumes.

Similar to lactose intolerance, the enzymes that break these compounds down are created by the lining of your small intestine. If you have intestinal damage, you may choose to limit these foods to see if symptoms improve or supplement with digestive enzymes while your gut heals.


How to Find Food intolerances and Sensitivities:

There are 3 methods I use to find food intolerances and sensitivities. It can take some time to find them all if you have several food intolerances, but in my opinion, it is well worth the effort!

1. Keep a Food Journal

This is one of the easiest ways to find a food intolerance and does not require changing your diet initially.

To keep a food journal:

  • Record everything you eat.
  • Note any symptoms you feel after a meal. I like to check in 2 hours after a meal or before eating my next meal.
  • Record any digestive symptoms as well as headaches, brain fog, or exhaustion.
  • After a week, review your food journal and look for patterns.

Tip: It helps to keep regular food patterns during this time. For example, eating the same thing for breakfast or lunch each day while searching for food intolerances will simplify the process.

Note: sometimes food intolerance symptoms won’t occur for 24-48 hours after eating a food. In this case, your results may be confusing. I recommend using the methods below to further investigate possible intolerances.

celiac diagnosis career

2. Try an elimination diet

An elimination diet means that you avoid eating a certain food for a period of time. You will need to remove the food in its natural form as well as products that use this food as an additive or flavoring.

How to do an elimination diet:

1. Choose food(s) to eliminate.

I recommend choosing only 1 or 2 potential food intolerances at a time. However, programs like The Whole 30 offer guided elimination diets for a large number of potential food intolerances. I personally find the Whole 30 to be too limiting in its early stages, but if you’re up for the challenge, many people swear by it.

2. Remove the suspected food(s) from your diet.

I like to begin an elimination diet at the start of the week for simplicity. Having a set start date rather than jumping in allows time to find replacements for these foods beforehand. Planning avoids stress and decision fatigue during the elimination trial and makes the whole process more pleasant.

I usually avoid these foods for 1-2 weeks, but some sources will suggest you wait a month or more.

3. Do a “food challenge”

When you begin eating the suspected food again, you can decide to simply add it back to your diet or eat a small amount of the food in question. The more you eat, the more obvious your symptoms will be.

You will likely need to eat more than a bite to notice symptoms. However, I don’t recommend diving headfirst into a large bag of corn chips or glass of milk. I recommend trying 5-7 tortilla chips or a half cup of milk at most on my first exposure post elimination trial. Then gradually increase the amount for the next challenge.

Helpful Tip: Wait at least 48-72 hours to observe your symptoms before doing another trial. This prevents confusion over which food you react to. It also prevents ‘fueling the fire’ if you react to the trial later than anticipated.

Note:  If you’re eliminating more than one food, only test one at a time. Once you made a decision on one food, you may begin food challenges with the others.

3. Get help from a professional

Medical doctors and Naturopaths can help guide you through this journey and perform several tests to identify possible food intolerances and sensitivities.

Food intolerances can be tricky to identify but are well worth the time and effort as part of the healing process. The improved physical energy, digestive symptoms, and mental clarity drastically improved the quality of my life and can help you too!

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With love and gratitude,

❤︎ Jamie

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Jamie has celiac disease down to a science!


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Jamie has celiac disease down to a science!

A fresh perspective on gluten-free with tips that are easy to implement!


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A fresh perspective on gluten-free with tips that are easy to implement!

The best GF info and ideas out there, especially if you travel! Wonderful pictures, as well.


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The best GF info and ideas out there, especially if you travel! Wonderful pictures, as well.

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I feel like can travel spontaneously again. Thank you!

I love the vibe - so positive and uplifting!


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I love the vibe - so positive and uplifting!
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