When and How to Start an Elimination Diet?

We will show you what an elimination diet consists of and how it can be implemented to detect intolerances to food groups or nutrients. You will also learn about its risks.
When and How to Start an Elimination Diet?
Saúl Sánchez Arias

Written and verified by the nutritionist Saúl Sánchez Arias.

Last update: 09 July, 2022

The elimination diet is put in place to detect food intolerances. There are a number of tests on the market that promise to test for these disorders, but they aren’t reliable.

There’s no evidence to support them. Therefore, in many cases, there’s no choice but to remove a particular food from the diet to see if there’s any improvement.

Before starting, it should be noted that there are food intolerances that are transient. This means that the body loses the ability to digest or absorb a certain nutrient for a certain period of time. There may even be a specific modification or intervention to improve the symptoms and accelerate the process.

How does an elimination diet work?

When we talk about an elimination diet we’re referring to a very restrictive plan that isn’t sustainable or healthy in the medium term. It has to be put into practice for a period not exceeding 3 weeks.

Otherwise, severe nutritional deficits may be experienced. Some of these could condition the correct supply of oxygen through the blood, as is the case of anemia. This is evidenced by research published in the journal The Medical Clinics of North America.

The first thing to do in the elimination diet is to avoid food groups that may be responsible for provoking intolerances. These include citrus fruits, nuts, legumes, gluten-containing foods, dairy, eggs, and spices. For two weeks, a diet will be recommended with fruit, non-solanaceous vegetables, and rice.

This part is the most complicated. In fact, we’re talking about a plan that involves an insufficient protein intake, which can affect the state of lean mass. According to a study published in the Annals of Nutrition & Metabolism, it’s necessary to consume at least 0.8 grams of protein per kilogram of body weight per day in order for the body to function properly.

After two weeks, the suspect food groups are introduced one by one and attention is paid to the symptoms. Intestinal alterations, headaches, or even dermatitis may appear.

Nuts and dried fruit aren't included in an elimination diet.
Nuts are part of the foods that are restricted in this plan, at least for 2 weeks.

Is it safe to do an elimination diet?

The elimination diet is applied when there are intestinal problems and the origin is unknown. It’s assumed that the cause is a certain type of food, or a group of them, in the worst case.

Therefore, the objective is to detect it in order to eliminate it. However, the application of this method has its risks, as we have already mentioned. Insufficient nutrient supply will lead to inefficiencies in the body’s physiological mechanisms.

It should be noted that many of the intestinal symptoms are caused by problems in the microbiota. Therefore, it may be a good option to try to improve the composition of the microbiota, instead of undergoing different types of dietary plans that can be detrimental to health. A suitable procedure would be supplementation with probiotics.

According to a study published in the journal Critical Reviews in Food Science and Nutrition, these microorganisms could help reduce the symptomatology of lactose intolerance, among others. In fact, many digestive and intestinal problems are conditioned by dysbiosis. This would require a direct intervention to restore the internal balance.

Irritable colon and intolerances

Before concluding, it’s important to note that many digestive problems can be caused by inflammatory pathologies in the intestine. One such example is irritable bowel syndrome.

It can lead to the appearance of intolerances later on, but, in reality, the cause would be this autoimmune disease. Therefore, the solution wouldn’t be in the total restriction of food groups, but in an approach that reduces inflammatory levels.

However, much is still unknown about these health problems. They’re considered chronic and have no cure.

They can only be managed through nutrition, with probiotics also being positive. Even in some situations it would be enough to limit fiber intake to experience improvements.

Intestinal microbiota.
More and more is coming to light about the microbiota, and so many current treatments aim to modify it to reduce digestive symptoms.

Beware of the elimination diet

The elimination diet is very restrictive in essential nutrients, so it isn’t sustainable in the medium term. It’s an approach that can help to locate an intolerance, but it isn’t necessarily the solution to the problem.

Before starting an approach of this type, it’s advisable to visit a specialist. There are other alternatives that can be implemented to rule out pathologies.

Good eating habits can often correct problems. It’s good to ensure the presence of fermented foods in the diet on a regular basis and to ensure an intake of at least 25 grams (1 oz) of fiber every day.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Massey A. C. (1992). Microcytic anemia. Differential diagnosis and management of iron deficiency anemia. The Medical clinics of North America76(3), 549–566. https://doi.org/10.1016/s0025-7125(16)30339-x
  • Richter, M., Baerlocher, K., Bauer, J. M., Elmadfa, I., Heseker, H., Leschik-Bonnet, E., Stangl, G., Volkert, D., Stehle, P., & on behalf of the German Nutrition Society (DGE) (2019). Revised Reference Values for the Intake of Protein. Annals of nutrition & metabolism74(3), 242–250. https://doi.org/10.1159/000499374
  • Oak, S. J., & Jha, R. (2019). The effects of probiotics in lactose intolerance: A systematic review. Critical reviews in food science and nutrition59(11), 1675–1683. https://doi.org/10.1080/10408398.2018.1425977

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.