Eliminate for Gut Health

Insomnia, fatigue, bloating, brain fog, joint pain, breakouts, rashes, migraines, bowel changes, GI pain, sinus issues…

… these are all symptoms that point to potential food sensitivities.


What’s the difference between a food allergy, food intolerance, and food sensitivity?

Food allergies occur as the result of the body’s immune system overreacting to some component of a food and perceiving it as dangerous. The immune system produces IgE antibodies in the presence of these foods which will bind to mast cells in the body tissues and release large amounts of histamine in response. Symptoms generally appear quickly after ingestion (sometimes within seconds) such as sneezing, itchy eyes, rash, swelling, or bronchial constriction. In severe cases, the body experiences anaphylaxis and possibly go in to shock.

Food intolerances do not involve the immune system at all. These are generally the result of a lack of a certain enzyme needed to properly digest a component of a food, such as in lactose intolerance in which the person lacks sufficient lactase enzymes. Symptoms are generally acute and related to the digestive system such as abdominal pain, bloating, or diarrhea and subside without a few hours.

Food sensitivities are also a response of the immune system, however they differ from allergies in that they cause the release of histamine into the blood rather than into body tissues. This means that the reaction can be delayed and with less obvious symptoms. Antibodies (IgG, IgE) may or may not be involved, but regardless of the mechanism involved the result is the consistent release of immune cell mediators due to continued exposure which can lead to chronic inflammation, pain, tissue damage, digestive disturbances, skin conditions, and has been linked with several disease states and autoimmune disorders. Symptoms may take days to cause a discernible reaction and can lead to any of over 100 symptoms relating to many different organs and systems of the body, making it difficult to identify the cause or offending foods.


How do you test for food sensitivities?

If you suspect that you may be reacting to a certain food. Simply remove it from your diet for several days, then reintroduce it and monitor your symptoms over the next 1-2 days. This would be the easiest way to test.

However, symptoms like indigestion, bloating, pain, and more tend to be chronic or frequent problems which can make it difficult to fetter out one single offending food. Also, individuals tend to have multiple food sensitivities at the same time, also making diagnosis difficult.

A strict elimination diet is the best method that we have available right now, however, even the most strict of diet may still contain foods you are reacting to, as most structured elimination diets only remove commonly reactive foods. Because every body really is unique, it’s important to work with a trained nutrition professional, like a registered dietitian, to help guide your elimination and reintroduction phases.

While food allergies are commonly tested for using a skin prick test, food sensitivity testing is less clear.

Some labs use blood tests looking for an IgG reaction (like ELISA) or a white blood cell reaction (like ALCAT). However, these tests are not the gold standard and have not shown good reliability and validity in clinical trials. Results can often be inconsistent – such as receiving different results from separate blood samples from the same person going to the same service for testing. This is why the elimination diet is considered the gold standard for testing food sensitivities.

And, above all else, food is not the problem with food sensitivities, THE PROBLEM IS YOUR GUT! Sensitivities are just a symptom of the underlying problem – an imbalanced gut. Food sensitivities are often caused by increased intestinal permeability, more commonly known as “leaky gut“. When the junctions between the cells lining our intestines because “loose”, they let things into the bloodstream that don’t belong there – like proteins that have not been completely broken down. These proteins are not normally present in the blood, and so the body reacts – it doesn’t recognize it as food, only foreign, and responds in stride.


Benefits and Features

  1. Identify food triggers – obviously, the major reason that first brings people to following an elimination diet. Reactions to food are frequently overlooked in their role in chronic health issues. Adverse reactions are common when the same foods are eaten repeatedly. The elimination diet is designed to omit foods that are generally consumed frequently.
  2. Reduce inflammation – reactions to food can trigger chronic low-grade inflammation in the gut, leading to increased intestinal permeability (“leaky gut”). This barrier breakdown can allow foreign substances into the blood stream causing more inflammation and immune system responses. Removing problem foods decreases inflammation and can help calm the immune response. Anti-inflammatory foods are promoted which also helps the gut to heal. Cells lining your intestine turnover every 2-4 days, so changes to the diet can produce noticeable differences in a short period of time.
  3. Supports healthy microbiome – more than 70% of the body’s immune system is in the gut, and it is constantly assessing what is going in to it. The way the immune system responds is influenced by your gut microflora. When the gut is inflamed, the balance of good vs. bad microbes is thrown off which results in improper stimulation of the immune response.
  4. Dairy-free, gluten-free – because many individuals experience adverse reactions to these foods, they are omitted in the elimination diet. Some of the problem with diary is the presence of lactose. An estimated 25-90% of the world’s population is lactase-deficient to some extent (depending on your ancestry). Fermented dairy (yogurt, sour cream) are much lower in lactose but still contain casein milk protein. There are different types of casein (A1 and A2 beta casein) depending on the type of cow and this can also impact tolerance (A2 is generally better tolerated), however this is still being investigated in terms of how they impact allergies, intolerances, and gut permeability, which is why all dairy is omitted. Gluten is a family of proteins found in a few major grains (wheat, barley, rye) and their associated products. Gliadins are proteins in gluten that can cause damage to the microvilli of the small intestine leading to leaky gut.
  5. Phytonutrients to heal the gut – the diet includes a variety of fruits and vegetables which provide phytonutrients and antioxidants – nutrients that promote healing and assists the gut, liver, and kidneys. Antioxidants protect against free radical damage. Phytonutrients also play a role in improving the body’s stress response and reducing inflammation. In general, it is recommended that vegetables have a greater emphasis than fruits to avoid excessive intake of natural sugars.
  6. Reduces toxic burden – artificial colorings, additives, preservatives, pesticides, herbicides, insecticides, sweeteners. These are all substances that, when consumed, your body needs to process and excrete. In addition to avoiding potentially reactive foods, it is also recommended to choose organic when possible to lower the workload of an already taxed system trying to heal. Grass-fed, pasture-raised, free-range, wild-caught sources of animal protein are also encouraged as they tend to be higher in omega-3 fatty acids. Intake of high-fiber foods and adequate hydration will also help.
  7. No calorie restriction – weight loss is not a goal, but may or may not happen along the way.
  8. Promotes body awareness to food – during the reintroduction phase, individuals develop an increased awareness of foods that trigger symptoms in their bodies. Taste buds may change and sensitivity levels may be reset.

foods to eat and avoid

What do I eat?

  • Proteins – low-mercury fish like halibut, herring, mackerel, salmon, sardines, and tuna (wild-caught, sustainable preferred); wild game like buffalo, elk, lamb, and venison; poultry like chicken, turkey, and Cornish hen; spirulina; select protein powders (hemp, pea, rice)
  • Legumes – peas, lentils
  • Dairy alternatives – coconut, almond, flaxseed, rice, hemp, or hazelnut milk (unsweetened without added gums)
  • Nuts and seeds – almonds, Brazil nuts, cashews, chia seeds, coconut, flaxseed, hazelnuts, hemp seeds, macadamias, nut and seed butters, pecans, pine nuts, pistachios, pumpkin seeds, sesame seeds, sunflower seeds, walnuts (raw, unsalted preferred)
  • Fats and oils – avocado, coconut milk, olives, coconut oil, olive oil, sesame oil, almond oil, safflower oil, sunflower oil, walnut oil, hempseed oil, flaxseed oil, grapeseed oil (unrefined, cold-pressed, organic preferred)
  • Vegetables – almost all (ideally at least 5-6 cups per day, fresh or frozen, organic preferred)
  • Fruits – almost all (fresh or frozen, organic preferred)
  • Gluten-free whole grains – amaranth, buckwheat, kasha, millet, quinoa, rice, teff (preferably certified gluten-free)
  • Beverages – filtered water, broths, meat stocks, decaffeinated tea, fresh vegetable juices, coconut water, seltzer water
  • Spices and condiments – all herbs and spices; mustard (without added sugar); homemade condiments (using approved ingredients); vinegars (raw apple cider vinegar, balsamic vinegar, white vinegar)
  • Sweeteners – (use in limited amounts) brown rice syrup, blackstrap molasses, pure maple syrup, raw honey, coconut sugar, agave nectar, lo han (monkfruit), erythritol, stevia


What foods do I avoid?

  • Proteins – beef/veal, eggs, pork, processed meats (cold cuts, canned meats, frankfurters), shellfish, whey, casein, soy (miso, natto, tempeh, tofu, textured vegetable protein)
  • Legumes – soybean products (edamame, miso, soy sauce, tamari, tempeh, tofu, soy milk, soy yogurt, textured vegetable protein)
  • Dairy – butter, cheese, cottage cheese, cream, frozen yogurt, ice cream, milk, non-dairy creamers, soy milk, yogurt (dairy and soy), whey, casein
  • Nuts and seeds – mixed nuts (with peanuts), peanuts, peanut butter
  • Fats and oils – butter, corn oil, cottonseed oil, margarine/spreads, mayonnaise, peanut oil, shortening, soybean oil
  • Vegetables – corn
  • Fruits – none
  • Grains – those containing gluten – wheat, spelt, barley, rye, bulgar, seitan, triticale, kamut, farro, and oats (due to cross-contamination concerns)
  • Beverages – alcohol, coffee, tea, soft drinks
  • Spices and condiments – most commercially-prepared condiments (due to added sweeteners and preservatives)
  • Sweeteners – artificial sweeteners, sugar (white sugar, high fructose corn syrup, brown sugar, sucrose, etc.)
  • Other – chocolate (cocoa)

When in doubt, if it’s not on the list, don’t eat it.

Other versions of the elimination diet are more exclusive, choosing to restrict some of the “allowed” items above and allow some of the “restricted” items above. Work with a functional medicine physician and registered dietitian to determine what version you should follow.

How do I do it?!

To help identify potential problem foods, the elimination diet is typically followed for 3-4 weeks, after which time individuals enter the reintroduction process.

Reintroduction involves adding foods back in to the diet one at a time and observing for negative symptoms. Foods that continue to produce symptoms should be avoided for an additional 3-6 months before being retested.

Once the gut is healed, many foods that initially caused sensitivities may be reintroduced without symptoms and reintroduction and expansion of the diet is important. A diet with a large variety of foods helps ensure that the body gets essential nutrients and is especially important for those who have digestive issues.

Reintroduction Phase

On the Day 1 of the reintroduction phase, choose whatever food you would like to test first. Eat 2-3 servings of that food throughout the day while continuing to eat foods on the elimination diet. During that day and the next, record any symptoms you experience. If there is no reaction during the two-day period, keep that food in to your food plan and choose a new food to reintroduce on Day 3. Continue this process until all foods have been tested.

If any food causes a reaction, stop eating that food immediately, wait until the symptoms subside, and then move on to the next food to test. You may retest this reactionary food at the end of testing or it may need to be avoided for an additional 3-6 months until retesting.

If you are unsure as to whether a reaction has occurred, challenge it again. Be sure to eat enough of the food to get a good challenge. If no reaction happens the second time, the food is most likely not a trigger food.

Foods to Be Reintroduced

Wheat, dairy, soy, corn, peanuts, eggs, beef, pork, and shellfish are the major food categories avoided on the elimination diet. While the order these foods are reintroduced is up to personal discretion, the remaining excluded foods should not be introduced until after the above have been challenged.

After testing the above foods, begin to challenge the remaining foods such as barley, rye, coffee/tea, alcohol, chocolate, and nightshades.

For each food, eat a pure form containing no additives or ingredients that have been eliminated such as sugar or preservatives (ex. 100% whole wheat pasta, fresh corn kernels, hard-boiled egg, edamame, shrimp, cooked barley).

When reintroducing foods like coffee, caffeinated beverages, chocolate, food additivites, or alcohol, make sure you are testing that food alone, which can be difficult because these foods are often mixed with other foods excluded on the elimination diet (ex. most chocolate bars contain sugars, a mocha drink contains both chocolate and coffee).

After initial testing, it may be useful to test individual foods within a single food group to see if there is sensitivity to certain forms of that food. For example, test cheese made from cow’s milk, sheep’s milk, and goat’s milk. Test yogurt and butter. Test sprouted wheat or ancient forms of wheat like einkorn. Use the same 2-day testing procedure described earlier.


Extra Credit

Sometimes, in additino to certain major allergens, individuals may react to other compounds in foods, such as histamines, oxalates, salicylates, and nightshades.


Remember when we talked about allergic reactions? Yup, histamine was mentioned then.  Histamine is made and stored in mast celsl and is released during exposure to an allergen, causing dilation of blood vessels, increased mucus, and bronchoconstriction producing symptoms such as itching, sneezing, headaches, asthma, and rashes.

Generally high-histamine foods include: bananas, chocolate, strawberries, tomatoes, pork, fermented soy products, egg whites, sauerkraut, cheese, sausage, spinach, ketchup, eggplant, alcohol, vinegar, canned fish, smoked meats, coffee, tea, leftover meat, and some food additives and preservatives like food colorings, BHA, BHT, and benzoates.

Histamine content varies due to storage and food age – so unripened foods would be lower and fresh foods would be lower compared to ripened or leftover foods.


Certain health conditions (like a predisposition for oxalate-based kidney stones) may mean that oxalates should be limited or avoided. Foods high in oxalates include: blackberries, blueberries, raspberries, strawberries, currants, kiwi, Concord grapes, figs, plums, spinach, Swiss chard, beet greens, collards, okra, parsley, leeks, quinoa, celery, green beans, rutabaga, tangerines, summer squash, almonds, cashews, peanuts, soybeans, tofu, soy products, wheat bran, wheat germ, cocoa, chocolate, and black tea.


Chemically related to aspirin, salicylates can be created synthetically and found in many medications. Certain perfumes, pesticides, and preservatives also contain salicylates. Many common foods produce them naturally, such as citrus fruits, berries, milk, tea, coffee, alcohol, sweet potato, mint, almonds, peanuts, avocados, olives, melon, apples, tomato, zucchini, asparagus, and cucumber.


Belong to the Solanaceae botanical plant family. Individuals with certain autoimmune diseases may have an adverse reaction to consuming nightshades.

Common nightshades: ashwagandha, bell peppers, eggplant, huckleberries, goji berries, hot peppers (chili, jalapeno, and habanero, as well as chili-based spices like cayenne, chili powder, crushed red pepper, and paprika), pimentos, potatoes (except sweet potatoes), tomatillos, and tomatoes.

The Institute for Functional Medicine. ifm.org

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