Elimination Diets: Everything You Need to Know
Elimination diets are used to help identify and treat food intolerances and sensitivities. They are also used in identifying food allergies. In this Forbes article, you will gain an understanding of what temporary food elimination diets are and how they help manage food sensitivities and allergies.
Elimination Diets: Everything You Need to Know
Bojana Jankovic Weatherly, M.D., F.A.C.P., M.Sc. Internal Medicine / Integrative Medicine
Aug. 12, 2022
If you believe you’re living with a food sensitivity, food intolerance, or a food allergy, you’re not alone—about 10.8% of U.S. adults have a food allergy, and food intolerances are estimated to affect up to 20% of the general population.
A food allergy is a very serious condition, and symptoms can be life threatening. If you believe you might be living with a food allergy, it’s essential to talk to an allergist before you do anything else. On the other hand, if you’re experiencing a food sensitivity or intolerance, an elimination diet may be a good first option to help you identify the culprit.
Here’s what you need to know about elimination diets, and why it’s important to seek the guidance of a medical professional before you start.
What Is an Elimination Diet?
Food allergies affect the immune system, and typically occur after exposure to certain proteins in food. Within minutes to hours after ingesting an allergen, symptoms can be anywhere from mild (such as swollen lips, flushed skin or rash, among others) to life-threatening (difficulty breathing and loss of consciousness). Food allergies are usually diagnosed and treated via an allergist.
On the flip side, food intolerances are non-immune reactions that usually begin in the digestive tract, and can occur when the body is unable to break down food properly. The symptoms of a food intolerance usually occur in the digestive tract as well; think abdominal cramps, vomiting and diarrhea. Unlike a food allergy, the severity of food intolerance symptoms tends to be directly related to the amount of a type of food ingested (i.e., one bite of ice cream vs a whole cup).
While food intolerances and food sensitivities are sometimes used interchangeably, food sensitivities refer to a non-IgE mediated immune response. While there is still no consensus on the immune pathways that cause these delayed sensitivity reactions, some studies show that IgG testing can help determine food sensitivities in certain chronic conditions. If you find that certain types of food, such as foods with gluten, seem to cause issues such as joint pain, fatigue, rashes or brain fog—you may be dealing with a sensitivity, rather than an intolerance.
Typically, an elimination diet is used to help identify and treat food intolerances and sensitivities, but is also sometimes used in identifying food allergies. During an elimination diet, you’ll stop eating certain foods for a period of time—common culprits include citrus, dairy, eggs, gluten, soy, peanuts and tree nuts, shellfish, beef and corn. Doing this allows you to identify food triggers that may be causing digestive symptoms and other health issues, says Vanessa Méndez, M.D., a triple board-certified gastroenterologist, internist and lifestyle medicine physician, and founder of the telemedicine practice Planted Forward.
After suspected trigger foods are removed for a specified period of time, they’re strategically reintroduced back into the diet, adds Kristian Morey, a clinical dietitian with the Nutrition and Diabetes Education program at Mercy Medical Center in Baltimore.
It’s important to note that an elimination diet is not a weight loss diet. Rather, it’s used as a tool to uncover food intolerances, sensitivities and allergies.
How Does an Elimination Diet Work?
Elimination diet protocols can vary among practitioners, explains Sharon Zarabi, a registered dietitian for the Katz Institute for Women’s Health and Director at Northwell Health,
“My approach varies based on my client’s current diet and their personality and relationship with food. I typically remove foods in phases (rather than all at once) and educate them so they know the why in what we are planning,” says Zarabi.
A popular example of an elimination diet is the low FODMAP diet, adds Dr. Méndez. The goal of this diet is to provide immediate symptomatic relief, identify trigger foods and then allow for a slow and mindful reintroduction of foods. “The acronym FODMAP stands for Fermentable Oligo-, Di-, Mono- saccharides and Polyols. These are tiny carbohydrates found in many foods [such as apples, broccoli, wheat, soy and foods containing high-fructose corn syrup] that can increase symptoms of irritable bowel syndrome and other GI issues,” explains Dr. Mendez.
It’s important to note that the FODMAP diet (as well as any other elimination diet) is not meant to be followed forever. And it should be guided by a medical professional who specializes in nutrition, Dr. Méndez adds. “Typically, the process of elimination is anywhere between two to six weeks, followed by the reintroduction phase,” she says. Following such an extreme protocol could impact your overall nutrition, so it’s important to keep the elimination phase to a minimum.
While elimination diets can vary slightly in terms of protocols and the exact foods taken out, the process typically includes:
The Elimination Phase
The initial phase of an elimination diet involves removing all forms of a suspected food (or group of foods) from your diet, including cooked, raw and protein derivatives, says Morey. Often, an individual will remove all suspected foods at once (such as cutting out all forms of dairy and gluten), before slowly phasing them back in.
This phase of the diet is followed for about two to four weeks—without any exceptions—so if you accidentally consume the food, it’s recommended you start over. Sometimes, symptoms may become worse before they begin to improve; this typically occurs within the first few days of beginning the elimination phase.
Zarabi encourages her clients to keep a food diary to track their symptoms during the elimination phase, which also helps them stay compliant. “We can review and collaborate together, and reassess what is working and what is not,” she says.
The Reintroduction Phase
After the designated elimination phase, possible trigger foods are systematically reintroduced into the diet to see if any adverse reactions occur, says Morey. However, if your symptoms persisted even with careful avoidance of suspected foods beyond four weeks, it’s time to consider other causes of your symptoms.
Before reintroducing eliminated foods, make sure you’ve been symptom-free for at least five days. Then, start with one food at a time. Dr. Méndez advises starting with a small amount of the food—even just one teaspoon—into your diet. If that’s tolerated well, continue to slowly increase the portion size.
Do this progressively until you reach a full serving of the food, or until you notice a threshold—or the amount of food that causes your symptoms to return, says Dr. Méndez. It’s best to limit the reintroduction phase to one new food every three days, as that’s the time it usually takes for symptoms to come back if they’re going to.
Benefits of an Elimination Diet
Participating in an elimination diet can help you to discover whether there are certain foods you are not digesting well or that your body is reacting to negatively, says Dr. Méndez. It also allows your health care provider to customize a new, long-term meal plan to help treat any chronic conditions you may have, like irritable bowel syndrome (IBS), rheumatoid arthritis (RA), inflammation, migraine headaches and eczema, adds Zarabi.
Risks of an Elimination Diet
Eliminating foods can cause nutritional deficiencies, warns Dr. Méndez. For example, if you’re restricting dairy, you may need to supplement with other sources of calcium. That’s why it’s so important to undergo an elimination diet under the guidance of a medical professional, such as a doctor with nutrition training or a registered dietitian.
“It is especially important to monitor how many calories you’re getting during this time and ensure you’re getting nutrient-rich foods throughout your meals,” adds Dr. Méndez.
Common Food Allergies and Intolerances
Over 90% of allergic reactions are caused by the following foods, according to Morey:
- Peanuts, Tree nuts, Eggs, Milk, Wheat, Sesame, Fish, Shellfish, Soy.
- Meanwhile, foods that tend to cause intolerance reactions include:
- Dairy products, Chocolate, Eggs, Flavor enhancers such as MSG (monosodium glutamate),
- Food additives, Acidic foods, Alcohol, Histamine and other amines.
If you believe you’re dealing with either an allergy, sensitivity or intolerance due to one of the above mentioned foods, talk to your doctor. Depending on your symptoms, they may recommend trying an elimination diet, or may want you to undergo allergy testing.
Is an Elimination Diet Right For You?
A variety of symptoms may be indicative of an adverse reaction to food, says Morey. These include asthma; migraines; skin conditions like rashes, eczema, and hives and gastrointestinal issues like flatulence, diarrhea and abdominal pain. So if you’re experiencing any of these symptoms, consider whether an allergy, intolerance or sensitivity could be at play.
In general, anyone who is experiencing issues with digestion or reactions that seem connected to food should talk with their doctor, as your doctor is the best person to decide what the appropriate diagnostic workup is, as well as if a specialist referral is necessary. If your doctor believes you should talk to a specialist, many individuals can work with a gastroenterologist to evaluate the underlying cause of their symptoms, explains Dr. Méndez. This way, Celiac disease, inflammatory bowel disease, pancreatic insufficiency and other conditions can be ruled out. Once you’ve been tested, your health care provider can help design an elimination diet to uncover specific foods that may be triggering your symptoms.