Crohn’s Disease Exclusion Diet (CDED) Review
What is Crohn’s Disease?
Crohn’s Disease (CD) is a type of Inflammatory Bowel Disease (IBD), which can cause chronic inflammation and tissue damage along any part of the digestive tract. Most commonly, individuals living with Crohn’s Disease experience this chronic inflammation and related issues in the last section of the small intestine (the ileum), and/or in the large intestine. At this time, it is not known exactly what causes IBD, but it is thought that its development is influenced by a combination of genetic and environmental factors. Interestingly, rates of IBD (Crohn’s Disease and Ulcerative Colitis) in Canada are among the highest in the world, with occurrence increasing in young children. [1]
The Role of Diet in Managing Crohn’s Disease
As a Registered Dietitian and someone living with Crohn’s Disease, it’s a given that I have a keen interest in the role diet plays when it comes to managing inflammation and symptoms of Crohn’s. Various diet approaches seem to work for different individuals, and to date, there isn’t a solid body of evidence to suggest that any one particular diet works exceptionally well for all. Having said that, a newer diet backed by clinical trials is showing promise in the management of Crohn’s- in some cases as a stand alone therapy, and in other cases, as an adjunct therapy to medication.
Today I will be covering the Crohn’s Disease Exclusion Diet (CDED) and what the research is saying about its efficacy in helping to manage Crohn’s Disease. As someone who does their best to follow this particular diet, I’ll also take you through some of the pros and cons I have noted along the way.
Crohn’s Disease Exclusion Diet (CDED)
The Crohn’s Disease Exclusion Diet is a three-phase elimination diet during which individuals restrict certain nutrients and food additives that are thought to have a negative impact on the gut microbiome. Additionally, in the first two phases, many other foods are temporarily eliminated to reduce irritation in the digestive tract and give it time to heal.
In Phase 1, food restrictions are the most strict.
Phase 2 is considered a “step-down” phase in which the foods list is expanded to allow a larger variety of fruits, vegetables, beans, lentils, nuts and seeds, and other proteins in small amounts.
Phase 3 is a maintenance phase that is followed long-term.
If an individual experiences a flare of their Crohn’s while in the maintenance phase of the diet, they can cycle down to Phase 1 to help regain remission, and work their way back towards the maintenance phase.
CDED is supplemented with a specific brand and type of enteral formula. Enteral formula is a nutritional formula that can be used in tube feeding, or it can be swallowed by mouth like other nutritional beverages. Clinical trials show that the enteral formula is not a critical component of the diet as far as inducing remission is concerned; in studies, reduction in inflammatory markers seems to be comparable in those who use enteral formula along with CDED, and those who complete CDED alone [2]. The enteral formula does however provide additional vitamins and minerals that CDED lacks, especially in the first two phases. It is important that individuals who choose to follow CDED without enteral formula use appropriate supplementation to ensure adequate nutrition, and seek support from their healthcare provider.
Clinical trials of CDED (with and without enteral nutrition) completed in child and young adult populations show that clinical remission was achieved in 70% of study participants [2]. Additionally, CDED with enteral nutrition was shown to aid in inducing remission in children and adults whose Crohn’s medications (biologic therapies such as Remicade), were not working effectively [3]. Clinical trials are currently underway to determine whether CDED supplemented with enteral formula can induce clinical remission of Crohn’s in adult populations. More information about this trial can be found here.
Pros of Following CDED
Additional Support: Individuals who choose to trial CDED can access additional support through the Modulife app and program. The platform offers a variety of recipes that are safe to eat in the three CDED phases.
Easy to Meal Prep: Due to the limited ingredients list in Phase 1 & 2, it is easy to have all ingredients on hand and to meal prep larger batches of food at one time.
Evidence: In clinical trials, CDED has been shown to induce remission in children and young adults.
Cons of Following CDED
Mandatory Foods: The diet includes a list of mandatory foods that must be eaten daily as they promote microbiome health and ensure adequate protein intake. A mandatory foods list poses a challenge to individuals who dislike or have allergies/intolerances to these foods. Additionally, the diet is not suitable for those following vegetarian diets as the mandatory foods include chicken breast and eggs.
Family Meal Planning: The diet poses challenges to family meal planning, as different meals will need to be cooked for the individual with Crohn’s and the rest of the family, especially in the first two phases of CDED.
Restriction of Processed Foods: Aside from rice and rice noodles, all packaged and processed foods are restricted in Phase 1 of CDED. This poses a challenge with meal preparation as commonly used sauces, spice mixes, canned or frozen ingredients, and baked goods are to be avoided.
Nutrient deficiencies: CDED poses a risk of nutrient deficiencies due to the restrictive nature of this diet. Individuals completing CDED should be monitored by a health professional, such as a registered dietitian.
Disordered Eating: The strict nature of this diet may pose a risk to individuals who have, are recovering from, or have a history of disordered eating.
Cost: If opting to supplement with enteral formula, be prepared to spend a substantial sum in Phase 1 of CDED, and a fair amount in the following phases. Additionally, boneless and skinless chicken breasts are the main protein source in CDED, which can be costly. Furthermore, only fresh fruits and vegetables are recommended in the first two phases, which can further drive up costs.
Take Away Message
To sum it up, CDED looks promising as a diet therapy for inducing and maintaining remission in children and young adults living with Crohn’s Disease. Studies looking at the diet’s effectiveness in adult populations are underway. Due to the restrictive nature of this diet, it is important to work with a Registered Dietitian or health professional who is knowledgeable in CDED and human nutrition to ensure the diet meets your body’s nutritional needs. If you are at risk for disordered eating, this diet may not be suitable for you.
Crohn’s manifests uniquely in each individual, and not everyone responds to the same medications and diet changes. Additionally other factors, such as stress and smoking, can worsen Crohn’s inflammation and symptoms. If you are beginning to explore the effects of diet on your Crohn’s symptoms, a food journal can help you to reflect on, and document how certain foods and drinks make your body feel.
By: Pauline Bakowski, MHSc, RD
Reviewed by: Kristie Pun, MHSc, RD & Cheryl Ching, MSc, RD
References
Crohn’s and Colitis Canada. 2018 Impact of Inflammatory Bowel Disease in Canada. Canada: Crohn’s and Colitis Canada; 2018. Available from: https://crohnsandcolitis.ca/Crohns_and_Colitis/documents/reports/2018-Impact-Report-LR.pdf
Sigall-Boneh R, Pfeffer-Gik T, Segal I et al. Partial enteral nutrition with a Crohn's disease exclusion diet is effective for induction of remission in children and young adults with Crohn's disease. Inflamm Bowel Dis. 2014;20(8):1353-60.
Dietary therapy with the Crohn's Disease Exclusion Diet is a successful strategy for induction of remission in children and adults failing biological therapy. J Crohns Colitis. 2017;11(10):1205-1212.
Further Reading
https://mymodulife.com/for-patients/
Disclaimer: Our blog content is for general education purposes and may not be suitable for individual health conditions. Please see your health professional or book an appointment with one of our dietitians for personalized health recommendations.
