The elimination-challenge diet is the gold standard for identifying food sensitivities and intolerances. It’s the fundamental tool for discovering foods that may be triggering symptoms like allergies, eczema, sinus conditions, joint pain, migraine headaches, brain fog and fatigue. For many patients, the benefits are unmatched, and being in control of identifying and removing problematic foods from their diet can be empowering and motivating.
The elimination-challenge diet is usually a win-win for both patient and doctor, but it’s not necessarily an easy undertaking for everyone. The process is straightforward, but it can be (as the name implies) a challenge. Patients may become discouraged or frustrated if the diet is too restrictive or if the process drags out too long. There are some tips and tricks, however, to increase patient success. Follow the guidelines below to assist your patients in discovering their food sensitivities and the triggers for the symptoms they so badly want to overcome.
The elimination phase
During the elimination phase, the patient removes the most common problematic foods, as well as any additional high-suspect foods, from his or her diet. The most common diagnostic elimination phase is three to four weeks. A good rule of thumb is to continue this phase until there is an obvious improvement in symptoms.
The best elimination diet strikes a balance between restriction and feasibility. The more restrictive the diet is, the more likely you will be able to identify offending foods.
The most important foods to restrict during the elimination phase include the most common allergens: gluten, dairy, soy, eggs, corn, soy and citrus. For those with chronic pain or autoimmune disease with joint pains, it’s wise to remove the nightshade vegetables: potatoes, tomatoes, eggplant, and peppers.
Finally, if there is not enough clinical improvement with the basic allergy-elimination diet, consider the foods your patient eats on a daily (or multiple-times-a-day) basis. These foods should be highly suspect in terms of creating food sensitivities. If a patient has bananas three times a day or turkey every day for lunch, for example, consider adding those foods to the list of restricted items.
The elimination phase will naturally promote detoxification, as the patient removes offending and inflammatory foods. Encourage your patients to drink plenty of water during this time.
The challenge phase
Once a patient has followed the elimination phase for an average of two to four weeks, it’s time to move on to the challenge phase. During this phase, the patient reintroduces one food at a time and watches for any adverse reactions. It’s helpful to have patients keep a diet diary during this time, including all the foods they eat as well as any symptoms they have.
It’s critical to reintroduce, or challenge, only one food every three days. Some food sensitivities are mediated by a delayed hypersensitivity reaction, so symptoms can take up to three days to appear. It’s also best to challenge foods in their purest form. For instance, if you’re challenging dairy, use plain cow’s milk. Don’t forget to challenge yogurt and cheese, but do this as you would other foods (i.e. every three days if no reaction). If you’re challenging gluten, use 100 percent organic, whole-wheat bread. If you’re challenging eggs, use hard-boiled or soft-boiled eggs. This approach eliminates confounding factors, such as multiple ingredients or food additives.
The amount of time it takes to complete the challenge phase will vary from patient to patient. The more foods you reintroduce, the longer the phase will last. The process will also take more time if the patient has a strong reaction to a food that is challenged early on, because he or she will need to wait until triggered symptoms subside before challenging the next food.
An Elimination-Challenge Diet Case Example
A patient presents with eczema and agrees to try an elimination-challenge diet. She follows the elimination phase guidelines described above, including cutting out the top allergens and most inflammatory foods from her diet.
After four weeks, her skin is clear, so she enters the challenge phase. She reintroduces hard-boiled eggs on day 1, eating an egg for breakfast, lunch, and dinner. She waits for three days, and no symptoms appear. On day 4, she introduces wheat. She eats a slice of whole-wheat bread for breakfast, lunch, and dinner. Nothing happens to her skin. She waits through day two and still no symptoms. On the third day after eating wheat, she wakes up with a flare of eczema. She has discovered that wheat is a trigger for her skin symptoms.
The patient then eliminates wheat until her skin clears again. At this point, she can reintroduce the next food, such as milk. She now knows to exclude wheat from her diet, and she may discover additional triggers as she completes the challenge phase.
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