How to do an elimination diet safely

You've probably heard of elimination diets, but what exactly do they entail?

An elimination diet is often prescribed to determine the root cause of an underlying condition or symptoms someone may be experiencing.

This way of eating does not focus on weight loss despite having the word "diet" in the name, and there are many misconceptions about their purpose and how they should be leveraged.

In this article we will discuss: 

  • What is an elimination diet?
  • Do elimination diets help PCOS?
  • What are the risks of an elimination diet?

What is an elimination diet?

An elimination diet can be beneficial in identifying foods that may cause symptoms such as diarrhea, bloating, gas, fatigue, and difficulty concentrating. Often, elimination diets are utilized as a diagnostic tool to determine whether an individual has a food allergy or whether certain foods are triggering inflammation associated with other chronic conditions (1).

If an individual develops chronic symptoms, healthcare providers commonly recommend this diet. An elimination diet is only meant to be followed for a short period of time, usually 4-8 weeks. The diet is divided into two phases, the elimination phase and the reintroduction phase (2).

Elimination phase

To determine whether symptoms go away, an individual restricts certain foods during the elimination phase (2). Common foods avoided are dairy, gluten, eggs, soy, nightshades, sugar, and seafood.

A person may be instructed to eliminate all foods at once, or restrict certain groups individually. Make sure to work with your healthcare provider about what may work best for your body and goals.

Reintroduction phase

Upon improvement of symptoms, the next step would be to reintroduce foods that were restricted. The aim is to determine if reintroducing certain foods triggers your symptoms again (1).

If it is determined that a specific food or food group seems to be linked to symptoms appearing or worsening, it will generally be recommended to avoid this food for a period of time. Some people often find they can reintroduce the food in time once their body's inflammatory response has calmed down. Others find that they do best without the food even after a long period of avoiding it.

It is important to talk through your goals with your Pollie care team or external healthcare provider to determine what your goals are. Say that you did an elimination diet and realize dairy seems to make your acne worse. If participating in your social life in the exact same way as your friends is important to you, then you may decide it is worthwhile to have pizza or charcuterie with your friends every so often and face a subsequent pimple or two. On the other hand, if breakouts negatively impact your mental health and body image, honoring this boundary and ordering different food than your friends may be your priority.

Elimination diets and PCOS

There is no evidence that PCOS is directly linked to food allergies and intolerances. However, adverse reactions to foods can cause inflammation in the body and potentially exacerbate symptoms. To determine if a particular food might be contributing to your symptoms, your healthcare provider may suggest trying eliminating certain foods (3).

People with PCOS tend to have higher markers of inflammation compared to people without the condition. Since gluten and dairy consumption are believed to contribute to chronic inflammation, reducing these foods is usually recommended to decrease inflammation associated with PCOS. 

Grain products such as wheat, barley, and rye contain gluten. Gluten sensitivity and Celiac Disease are both gluten-related disorders. Gluten-containing foods trigger the body's immune system to attack the small intestine, leading to Celiac Disease. In contrast, people who are sensitive to gluten present a variety of symptoms when consuming gluten-containing foods, but do not have celiac disease or a wheat allergy. PCOS is not caused by gluten sensitivity or celiac disease, but it is often associated with inflammation in the body, such as leaky gut and other gastrointestinal problems, thus removing gluten could decrease overall inflammation (4). 

In addition to PCOS, many people with this condition have a sensitivity to casein and whey, both of which are found in dairy products. Like Celiac Disease and gluten sensitivity, consuming dairy can damage the intestinal wall lining and cause inflammation (5). Individuals who remove gluten or dairy report feeling better, but there's no evidence that doing so is helpful for PCOS (3).

Risk of elimination diets and tips for maintaining a healthy attitude toward food

It is important to remember that what may work for one person may not work for another. Following an elimination diet is restrictive and should only be performed under the supervision of a healthcare professional for a short period of time.

An elimination diet carries certain risks, including creating a fear of food or malnutrition if done for a long period of time. If you have a history of an eating disorder or even just disordered thoughts around food, an elimination diet may not be for you.

A care team like what Pollie offers can guide you through an elimination diet while still meeting your nutrition needs if you suspect a particular food may be contributing to your symptoms. 

In general, the following tips can be helpful when it comes to doing an elimination diet safely:

  1. Find a provider who has helped patients do elimination diets before in a healthy way. As mentioned, elimination diets should only be done under the supervision of a healthcare professional. Working with a physician who is functionally-trained, or a reputable nutritionist like a certified nutrition specialist (CNS) or registered dietitian (RD), is a good place to start. It is important that you trust your provider is overseeing your elimination diet with the overall goal of identifying the root cause of your health issue. It may even be worthwhile to ask them what they think elimination diets are best used for and how they make sure their patients do not develop disordered eating habits from an elimination diet. If there is an emphasis on weight loss or diet culture (e.g., they use blanket statements about foods or entire food groups being “bad” for our health) you should likely raise an eyebrow.
  2. Continually remind yourself of the purpose of elimination diets and be honest with yourself about your goals. These types of diets are meant to help you uncover the root cause of a health issue, not to lose weight. While some people may find that they do lose weight as a result of an elimination diet, it should be a result of their body having less inflammation, not because they have been restricting calories. Even if you enter an elimination diet with a health-specific goal (e.g., optimize fertility, improve your long-term health, heal your gut issues) it can be easy to lose this throughout the course of the diet. Even when done with a well-intended purpose, practicing restriction and keeping your mindset healthy is hard! If you find all of your goals do center on weight loss and appearance and not necessarily health, this may be a warning sign that you are slipping into disordered patterns.
  3. Do not strive for your elimination diet to be a lifestyle. Recall that elimination diets are temporary, and in many cases, people can add “problem” foods back in once their gut has had the chance to heal itself. Even if you find your body never fully tolerates a food, it is up to you to weigh the cons and benefits of eating that food in the future. For example, you may find that dairy aggravates your acne. While you may not choose to eat it every day knowing that, the social connection "benefit" of having pizza with friends (knowing that it may cause a breakout!) may outweigh the con of said breakout. You may find that the knowledge an elimination diet provides you with is more empowering in and of itself than the “results” that eating a 100% “perfect” diet provides. 
  4. Be on the lookout for disordered eating patterns. Preoccupation with meals and snacks, feeling guilt or shame around food, altering social plans that involve food, and other signs are all warnings of disordered eating. If you find yourself developing these thought patterns or behaviors, it is recommended that you stop your elimination diet and seek support.


  1. Gordon, Barbara. “What Is an Elimination Diet.” Eat Right, 13 Aug. 2019, 
  2. Rindfleisch, Adam. “Elimination Diet.” Elimination Diet - an Overview | ScienceDirect Topics, Integrative Medicine (Second Edition), 
  3. Grassi, Angela. “Food Intolerances May Make PCOS Symptoms Worse.” Verywell Health, Verywell Health, 25 May 2020, 
  4. Barbaro, Maria Raffaella, et al. “Recent Advances in Understanding Non-Celiac Gluten Sensitivity.” F1000Research, vol. 7, 2018, p. 1631., 
  5. Phy Ali M, Jennifer L. “Low Starch/Low Dairy Diet Results in Successful Treatment of Obesity and Co- Morbidities Linked to Polycystic Ovary Syndrome (PCOS).” Journal of Obesity & Weight Loss Therapy, vol. 05, no. 02, 2015, 

Simona Carputo


Simona is a Certified Health Education Specialist specializing in nutrition and health education. Simona is passionate about helping others develop a healthy relationship with food and manage chronic health conditions by implementing a non-restrictive approach to health.