How to Identify a Food Sensitivity with a Food Elimination Diet

As we say often here at WellBe, the things you choose to put in your mouth have a bigger impact on your health than anything else. So if you’re experiencing mysterious symptoms or chronic issues and can’t figure out why, a food sensitivity could be the culprit. Of course, we all eat a huge variety of different foods each day, so figuring out the source of your symptoms can be tricky. Enter: elimination diets. Read on to learn the benefits of a food elimination diet, best practices for how to do an elimination diet, and even a basic template for your own elimination diet plan. 

You can also listen to Adrienne read this guide on The WellBe Podcast. 

Using Diet to Unearth a Food Sensitivity 

By some estimates, 20% of people have some sort of food sensitivity or intolerance — though of course not all of them know that. A food sensitivity or intolerance might cause digestive issues like bloating, gas, diarrhea, constipation, and nausea; skin issues like rashes, itching, or hives; headache; fatigue; and even trouble concentrating or brain fog. Because the symptoms of a food sensitivity vary so widely and are often similar to symptoms of other conditions, these warning signs can be easy to miss. But if you think diet might be the root cause of your issues, elimination diets are the gold standard for unearthing a food sensitivity or sensitivities. 

You may have heard of IgG food sensitivity tests, which look for food sensitivities through blood samples, and it’s tempting to reach for a quick fix rather than going through the effort of a food elimination diet. However, these tests are not only quite pricey, but also unproven. In fact, the Canadian Society of Allergy and Clinical Immunology, the American Academy of Allergy Asthma and Immunology, and the European Academy of Allergy and Clinical Immunology have all issued position statements against their use. 

That leaves us with elimination diets. An elimination diet works by removing foods from your diet that you suspect you might have a food sensitivity to. After several weeks of elimination, you reintroduce the foods one at a time, tracking your symptoms along the way so that you can identify anything you don’t tolerate well. Once you’ve identified any trigger foods, you cut them out of your diet permanently. 

When you consume a food that your body doesn’t tolerate well, it triggers inflammation in your gut and immune system. Elimination diets work because they remove the trigger, allowing inflammation to slowly go down and restoring normal function in your body. When you begin reintroducing foods, then, you’ll be able to clearly notice if any old symptoms flare up. 

The logic behind elimination diets is straightforward, and it works. In one study, people with IBS who followed an elimination diet had up to a 26% greater reduction in symptoms than those who did not. Other studies have found that elimination may reduce symptoms of ADHD, eczema, and migraines. And for those without specific diagnoses like these, elimination diets can bring some clarity to seemingly mysterious issues like poor digestion, fatigue, and skin problems. 

How to Do an Elimination Diet 

Now that you know the benefits, let’s look at some guidelines on how to do an elimination diet.

Decide what type of elimination diet you’ll do. 

There are a ton of different types of elimination diet plans to choose from. Some are geared around specific conditions (for instance, IBS or autoimmune disease), some are trendy challenges (like Whole30), and others simply provide a loose structure for finding a food sensitivity, whatever it may be.

Some of the most well-known types of elimination diet plans are:

• Low-FODMAP: This elimination diet plan is great for people with IBS and SIBO. It involves removing FODMAPs, which are short-chain carbohydrates that some people can’t digest. What’s tricky about FODMAPs is that there aren’t any real rules or logic to help you know what falls into that category — for instance, asparagus is a FODMAP but green beans aren’t; cherries are a FODMAP but grapes aren’t; cashews are a FODMAP but walnuts aren’t; and on and on. 
• Autoimmune Protocol (AIP): AIP is an elimination diet plan designed to reduce inflammation caused by autoimmune disease. While on this diet, you eliminate grains, legumes, eggs, dairy, nightshades, and processed foods, among other items. It can help with autoimmune conditions like IBD, Hashimoto’s, and leaky gut syndrome.
• Whole30: Whole30 is an approach to eating that you’re probably used to hearing about around New Year’s, when everyone is sharing their resolutions to eat healthier. As the name implies, it’s a 30-day plan in which you eliminate many of the same foods you eliminate with AIP, as well as alcohol. 
• GAPS Diet: Gaps stands for Gut and Psychology Syndrome, and it is an elimination diet aimed at treating conditions that affect the brain, like autism. It involves eliminating sugar and artificial sweeteners, alcohol, processed food, grains, dairy, caffeine, and soy, among other items. 
• Just one food: This type of elimination diet plan involves eliminating just one food or food group. For instance, you could do a dairy elimination diet, or a gluten elimination diet. This is the easiest way to do an elimination diet, as it’s the least restrictive. However, if you have more than one food sensitivity, this approach might not be best.
• Different foods over a period of time. This is a much longer elimination diet plan than most others, as it involves four different phases of roughly 30 days each. During each phase, you eliminate a few different foods or food groups. By the end of all four phases, you’ll have done a thorough elimination diet, but you’ll never feel extremely restricted because you’re only eliminating a few foods at a time. It’s a bit complicated, so check out this template. 
• The Few-Foods Diet: The Few-Foods diet is an extremely simplified, restrictive type of elimination diet in which you only eat a selected list of foods, usually foods that you don’t commonly eat. Because this diet is so restrictive, it should only be followed for a short period of time. 

Know how long it will take.

An elimination diet plan is not a lifestyle. It is a tool that you can use to unearth a food sensitivity, and then you can adjust your lifestyle accordingly. A food elimination diet is, by nature, quite restrictive, and following one for a prolonged period of time could cause nutrient deficiencies.That said, it’s important to eliminate any potential trigger foods for at least three weeks. This is important because when your immune system reacts negatively to a food, it creates antibodies, and these antibodies take around 21 days to clear your system. If you do a food elimination diet for a shorter period of time than three weeks, your body won’t be able to get back to baseline, making it impossible to identify a food sensitivity as you start reintroducing eliminated items. 

Understand the different phases.

Each elimination diet plan has three phases: planning, elimination, and reintroduction. Let’s get into them:

• Planning: In the planning phase, you decide what foods you’ll be eliminating (or if you’re going to follow a specific diet plan, like AIP or Whole30). Remember that the most restrictive plans are the most likely to unearth an unknown food sensitivity, but they’re also the most difficult to follow. 
• Elimination: This is the longest phase, and the one in which you actually eliminate all of your suspected trigger foods. If you slip up — even a small slip-up — your body will go back to square one and you’ll need to start over, so total compliance is important. During this phase, you should keep a detailed journal of what you’re eating, how you’re feeling, and what symptoms you’re experiencing. Include things like your stress level, how much sleep you’re getting, how your digestion is, etc. You can use old fashioned pen and paper, or a symptom-tracking app.  
• Reintroduction: Once you’ve completed your three weeks (at least) of elimination, it’s time to reintroduce foods one by one. Each food or food group should be introduced individually over the course of two to three days. This is important because you want to be very clear on which food you are reacting to, if you have a reaction. If you eat gluten and dairy too close together and feel sick, you may not be able to know for sure which food is causing a reaction and have to do the whole elimination phase over again to find out. On the other hand, if you experience no symptoms during those two to three days of reintroduction, then you can cross that food off your list of potential food intolerances and move onto the next. If you do experience symptoms, then you’ve successfully identified a food sensitivity. Congrats! But remember that this doesn’t mean it’s your only sensitivity — continue to individually reintroduce the other foods and track your symptoms.

Have some coping strategies. 

Elimination diets are hard. Make sure you’re equipped to handle it with these best practices:

• Keep your blood sugar stable: When your blood sugar dips and spikes, you’ll experience hunger and cravings, making it more difficult to stick to your meal plan. Make sure to eat a filling combination of fats, proteins, and carbohydrates at every meal and snack to regulate your blood sugar.
• Tone down your social schedule: Before you begin, make sure you don’t have any can’t-move social engagements during your elimination diet (for instance, a fancy dinner at a restaurant, or a wedding where you know you’ll want to have a glass of wine). Once your calendar is free and clear, be careful about overcommitting and putting yourself in situations where it might be difficult to stay compliant. This might mean being a bit of a hermit, bringing your own food to social gatherings, or planning activities that don’t include food, like a walk with a friend. 
• See it through to the end: Remember that the reintroduction period is just as important as the elimination period. If you dive right back into french fries and cookies after the elimination phase is over, then all the hard work you’ve done will be for nothing. Stick with a slow reintroduction to figure out what foods your body doesn’t like.

Putting Together Your Elimination Diet Plan

Now that we’ve gone over the general advice on how to do an elimination diet, let’s get into the specifics. 

As we mentioned above, the most restricting elimination diet plans are the ones that are most likely to help you identify food sensitivities. But that said, every person is different, not only in terms of their symptoms, but also their lifestyles and unique nutritional needs. Because of that, there is no one-size-fits-all elimination diet plan. Use the information in this section as loose guidelines for figuring out what works best for you.

The first step is to decide what you’ll eliminate. If you think you may have an autoimmune disease or IBS or some other specific condition, it might make sense to follow one of the diet plans listed above (for example, AIP for an autoimmune condition, or Low-FODMAP for IBS). If you just suspect that you might have a food sensitivity but don’t know what it might be, however, there are other ways to figure out what to eliminate:

• Keep a food journal. Write down everything you eat for a week, as well as any symptoms you experience throughout the day. This might let you identify patterns or potential trigger foods.
• Get honest with yourself. Ask yourself some important questions, such as what foods do you tend to crave? What foods do you eat most often? Which foods would you have trouble giving up? Unfortunately, the foods that hold the most power over you are sometimes the ones you need to get rid of.
• Try the common culprits. While you could have a food sensitivity to anything, some foods are more commonly associated with allergies or intolerances. These foods are often excluded in elimination diet plans, and are a good place to start: gluten, dairy, soy, eggs, corn, and nightshades.

If you’re following a specific diet, like Whole30 or AIP, you’ll be able to easily find an elimination diet plan online, complete with meal plans and recipes. But if you’re going a bit more freestyle, here are some guidelines on doing a basic elimination diet plan.

If you’re making up your own food elimination diet plan, it makes sense to eliminate the most common allergens: gluten, soy, dairy, eggs, shellfish, tree nuts, peanuts, corn, alcohol, caffeine, processed foods, sugar, and artificial sweeteners.

For three weeks, all of these foods should be on your “No” list. Below are some meal and snack ideas for your elimination phase:

Breakfast

• A berry smoothie with coconut milk (make sure it is unsweetened)
• Gluten-free oatmeal with fruit and coconut yogurt (make sure it is unsweetened)
• Breakfast taco with beans and/or lean meat, gluten-free tortilla (just make sure it doesn’t contain corn), and avocado
• Organic, nitrate-free chicken or turkey sausage or wild smoked salmon, veggies sauteed in coconut or avocado oil, and roasted sweet potatoes or sautéed spinach

Lunch

• Arugula salad with white beans, shredded organic chicken, and lemon vinaigrette (make sure it is unsweetened)
• Organic chicken salad sandwich with vegan mayo on gluten-free bread
• Hummus and roasted veggie sandwich on gluten-free bread
• Tabbouleh salad with cubed tempeh

Dinner

• Grilled organic chicken, cauliflower rice, veggies sautéed in coconut or avocado oil
• Roasted veggie and black bean tacos with avocado
• Buddha bowl with chickpeas, quinoa, and veggies
• Grass-fed burgers with lettuce “buns” and roasted sweet potatoes

Snack

• Fresh fruit
• Unsweetened coconut yogurt with pumpkin seeds
• Gluten-free crackers with hummus
• Slices of cucumber or celery with guacamole 

Once you’ve completed three full weeks of your elimination diet, introduce your eliminated foods one by one. Remember to allow two to three days for each reintroduction and eat the food being reintroduced at nearly every meal to make sure you’re going to have a reaction if you are in fact sensitive. Then look for any symptoms or changes in how you feel. 

The WellBe Takeaway on Doing a Food Elimination Diet 

The idea of an elimination diet can be intimidating, but for some people, it can be incredibly beneficial. Here’s what to remember about how to do a food elimination diet to identify a food sensitivity:

• Up to 20% of people have some sort of food sensitivity or intolerance, but many aren’t aware of that fact. If you’re experiencing chronic symptoms with no obvious cause, a food sensitivity might be to blame.
• Symptoms of a food sensitivity include digestive issues (bloating, nausea, constipation, gas, etc), skin problems (rashes, hives, itching), fatigue, and brain fog, among others.
• While blood tests exist to identify food intolerances, they are unproven and expensive. A food elimination diet is still the gold standard for sussing out any sensitivities you might have.
• When it comes to how to do an elimination diet, there are three phases: planning, elimination, and reintroduction. During the planning phase, you decide what food or foods you’ll eliminate; during the elimination phase, you spend three weeks (minimum) excluding your chosen foods; during the reintroduction phase, you introduce the eliminated foods one by one, allowing two to three days for each food and noting any changes in symptoms. If you react negatively after reintroducing a food, you’ve successfully identified a food sensitivity.
• There are many specific elimination diet plans, like Whole30, AIP, and Low-FODMAP. You can follow one of these specific diets, or create your own elimination diet plan based on the specific foods you want to eliminate.
• Some of the foods and food groups that are most commonly associated with food allergies (and so a good place to start if you don’t have any suspicions about what you might be sensitive to) are gluten, soy, dairy, corn, eggs, shellfish, and nuts (both tree nuts such as almonds, walnuts, cashews, pecans and peanuts, which are technically not a nut but rather a legume).

Have you ever done a food elimination diet? How did it go for you? Tell us in the comments below!

Listen to this guide on The WellBe Podcast.

Citations:

1. Nelson M, Ogden J. An exploration of food intolerance in the primary care setting: the general practitioner’s experience. Soc Sci Med. 2008 Sep;67(6):1038-45. 
2. Atkinson W, Sheldon et al. Food elimination based on IgG antibodies in irritable bowel syndrome: a randomised controlled trial. Gut. 2004 Oct;53(10):1459-64. 
3. Nigg JT, Holton K. Restriction and elimination diets in ADHD treatment. Child Adolesc Psychiatr Clin N Am. 2014 Oct;23(4):937-53. 
4. Dhar S, Srinivas SM. Food Allergy in Atopic Dermatitis. Indian J Dermatol. 2016 Nov-Dec;61(6):645-648. 
5. Alpay K, et al. Diet restriction in migraine, based on IgG against foods: a clinical double-blind, randomised, cross-over trial. Cephalalgia. 2010 Jul;30(7):829-37.