Elimination Diets: A Brief Overview on Their Purpose

What do keto, paleo, vegetarian, vegan, and Whole30 diets have in common?

Each one of these diets is an elimination diet.

An elimination diet is any diet that restricts you from eating certain foods or food groups. While elimination diets are traditionally used to diagnose and treat food intolerances, their popularity has grown to the extent that they are commonly used for other purposes.

You might have heard from friends, colleagues, or professionals that they have tried one of these diets and seen amazing benefits. However, elimination diets are not one-size-fits-all.

It is important to consider the purpose of elimination diets and to weigh the potential benefits and risks before deciding if it is right for you.

Purpose of Elimination Diets

Elimination diets are the gold standard for identifying food intolerances and sensitivities, and they can help detect food allergies too¹. By cutting out suspected “trigger foods,” or foods that trigger symptoms, you can test whether symptoms in fact disappear when those foods are removed.

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In addition to their diagnostic uses, elimination diets can be used to treat a wide variety of conditions, including allergies or intolerances, eosinophilic esophagitis², celiac disease³, certain skin conditions⁴, ulcerative colitis and Crohn’s disease⁵, Irritable Bowel Syndrome (IBS)⁶, and epilepsy⁷.

Once a diagnosis is obtained, following an elimination diet to avoid foods that cause or exacerbate symptoms can help treat the condition.

Elimination diets may also be followed for ethical, cultural, or religious reasons. For example, Islamic and Jewish dietary laws both prohibit consumption of pork. Another example is that many people limit their food choices to restrict animal products, not because they have an intolerance to these foods but because they think it is an ethically responsible choice.

Just like medical diagnoses, these are perfectly valid reasons to follow elimination diets.

Disadvantages of Following an Elimination Diet

Although following an elimination diet can yield many benefits, such as identifying trigger foods, treating conditions, fitting your personal or cultural lifestyle, there are also potential harms to consider.

Perhaps most importantly, restricting certain foods or food groups can put you at risk for inadequate intake of certain nutrients. For example, following the paleo diet may put one at risk of low intake of multiple nutrients⁸.

If you avoid certain foods or food groups long-term, it would be wise to research potential nutrients of concern for you and to supplement accordingly. Elimination diets may have other harmful consequences depending on the specific foods or food groups that are eliminated, as well as individual factors, such as age. For example, restricting carbohydrates may impact adolescent health to the extent that pubertal onset may be delayed⁹.

Related: Misunderstood Macros - 10 Lies You've Been Told About Carbohydrates

Additionally, elimination diets cannot differentiate between a food sensitivity and a food allergy. To test for a food allergy, blood testing for immunoglobulin E (IgE), an allergy-related antibody, is key. It should be noted that food sensitivity tests that work by detecting immunoglobulin A (IgA) or immunoglobulin G (IgG) also do not differentiate between food allergies or sensitivities and are not considered reliable.

For food sensitivities, elimination diets are the preferred choice rather than food sensitivity tests.

When to Use Elimination Diets

Should you follow an elimination diet? If you have unexplained digestive issues, such as gas, bloating, diarrhea, constipation, abdominal pain, or other symptoms that you think may be related to digestive issues, then you may want to consider trying an elimination diet. As food intolerances may affect anywhere from 1 in 50 to over 1 in 5 people¹⁰, it may be worth It for many of us to try an elimination diet if there are relevant symptoms present.

However, digestive issues are common in athletes for many reasons, including inflammation stemming from an intense workout regimen¹¹, limited gut microbiota caused by limited diet variety, or even from supplements.

Herbal and dietary supplements used for weight loss, bodybuilding, or other reasons can even cause liver injury¹². Digestive symptoms may or may not be treated with elimination diet depending on the underlying cause of the symptoms.

If you do not have digestive issues or a food intolerance but rather are considering an elimination diet to see if it will help you achieve a certain fitness goal, such as losing weight, then you will not succeed unless the elimination diet is combined with other lifestyle changes.

Elimination diets are useful for many things, but restricting foods or food groups will not help you lose weight; restricting calories, however, will.

How to Follow an Elimination Diet

Elimination diets should always be followed under the guidance of a health professional. It is often advised to keep a food diary for a week or more to see what foods you might need to eliminate. On the other hand, you might choose to follow a set protocol, cutting out common trigger foods such as gluten, dairy, or FODMAPs (Fermentable Oligo-, Di-, Mono-saccharides And Polyols).

For at least two weeks, you should follow the elimination diet, avoiding any of the potential trigger foods. Symptoms may resolve by the second week, but some protocols advise following the elimination diet for a longer period of time. For example, Whole30 was designed to be followed for 30 days before reintroducing potential trigger foods.

If symptoms improve, you can try challenging your body by reintroducing the previously eliminated foods one at a time. It is good practice to reintroduce the new foods or food groups every 3 days or so. You can start with just a small amount of the challenge food in case symptoms develop.

If symptoms do not resolve after eliminating possible trigger foods, then you will need to consult with a professional, as your symptoms may be due to different foods or causes unrelated to food.

Elimination diets should not be followed indefinitely but just until trigger foods are identified. Any foods that do not cause symptoms can be reintegrated into your normal diet.

Summary

Elimination diets are designed to diagnose and treat health conditions. If you suspect food intolerances or have unexplained digestive issues, an elimination diet can be useful to detect the cause of your symptoms and ameliorating your symptoms in the long run. Elimination diets may be chosen for cultural or personal reasons too.

On the other hand, an elimination diet should not be followed because it “worked” for someone else. I would caution against following orders from health professionals or “coaches” who prescribe an elimination diet simply because it worked for them. Just because someone has a medical diagnosis that can be treated by elimination dieting doesn’t mean an elimination diet can help treat similar symptoms in others.

You do not need to follow an elimination diet unless you have a condition that can be treated accordingly. Due to the risk of inadequate nutrient intake, it is important not only to consult with a health professional before trying an elimination diet but also to use common sense.

Unfortunately we live in a time when even health professionals may take certain extreme stances regarding diet. For instance, you might have noticed that professionals may advocate for ketogenic diets or plant-based diets for all individuals. However, there is no elimination diet that is suitable for everyone.

All foods are meant to be eaten unless you have a medical, cultural, or ethical reason to avoid them.