I was diagnosed with Crohn’s disease in 2021. When I was diagnosed I had no idea what Crohn’s was. If, like me, you’re not so sure what this elusive disease is, inflammatory bowel disease is an umbrella term to describe disorders that cause chronic inflammation of the gastrointestinal (GI) tract. The two most common forms of this are Crohn’s disease and Ulcerative Colitis. 

At this time, there is no cure for IBD; treatment is directed at helping patients to manage symptoms. Some of the symptoms include diarrhoea, abdominal pain, rectal bleeding, weight loss, and fatigue. 

While medical intervention is often essential in getting patients to remission, it can be helpful to also look at diet and lifestyle factors. For instance, stress is a major trigger for causing a flare of my disease, and eating anything spicy will definitely set me off. It tallies that how we live day-to-day, and what we feed our bodies, can either help or hinder the severity of our symptoms. 

Before we take a look at the benefits of a plant-based diet specifically for IBD, it’s important to emphasise that none of us in the IBD community are at fault for our diagnosis. It’s upsetting, speaking as someone with Crohn’s disease, when articles appear that suggest our food or lifestyle choices have directly resulted in the onset of disease. That is simply not the case. 

I want to take a look at the role of fibre, ultra-processed foods and animal protein in relation to IBD. 

Fibre

We get dietary fibre from plants, and it is naturally found in foods such as beans, fruits, nuts and whole grains like brown rice or barley. 

There’s a common misconception that a “low fibre” diet is appropriate for all people (and at all times) with IBD. A low fibre diet is essential when you’re preparing for a colonoscopy and it’s advisable when you are in a severe flare or have strictures (narrowing of the intestinal walls due to repeated inflammation and healing.) Bulking out intestinal content in this instance might cause symptoms that feel uncomfortable. 

However, if you have active disease in a mild flare or are in remission, some fibre is beneficial. Fibre lowers cholesterol, helps stabilise blood sugar levels and feeds healthy gut bacteria. It also provides a source of energy to the cells that line the gut and helps maintain the integrity of the gut barrier.

In a small study, 11 Crohn’s disease patients with moderately active disease were given 3g insoluble and 9g soluble fibre per day. Previously, they had been on a low fibre diet, but after increasing fibre intake, all 11 patients reported an improvement in symptoms, including reduction of diarrhoea, pain, urgency, incontinence and improved overall quality of life. 

Ultra-processed foods 

Ultra-processed foods account for 56.8% of total energy intake in the UK diet. Not only do processed foods predispose people to develop IBD, but aggravate the disease process too. 

Processed foods contain salt and sugar, harmful chemicals like Polysorbate 80 and Maltodextrin - emulsifiers that make foods shelf stable and taste creamy. They can be found in things like frozen desserts, cottage cheese and some canned foods. These chemicals can cause unfavourable, pro-inflammatory changes in the gut microbiome (GM) and reduce the gut’s defences against harmful bacteria. 

Generally, a higher level of GM diversity is associated with better overall health. Having a more diverse GM specifically increases our resilience to infection, impacting the effectiveness of our immune responses - in fact, 70-80% of the immune system is housed immediately behind the gut wall. For this reason, eating a wide variety of predominantly plant-based whole foods is going to be beneficial for your GM.

Animal protein 

Studies have shown that reducing the amount of meat and dairy in a diet can improve symptoms of IBD. A review in 2019 in The Permanente Journal showed animal-based diets to be consistently associated with a lower diversity of gut bacteria and an increase of mucus-degrading bacteria that irritates the gut barrier. 

One of the most compelling studies that I’ve read shows that active Crohn’s disease can be treated with a diet that restricts animal protein, fat, dairy, emulsifiers and food additives. 

In one of these studies, researchers reported on a group of patients, some with newly diagnosed Crohn’s disease and some with established Crohn’s disease, who were resistant to immune suppression medications. All were in a moderate to severe flare of their disease.

The researchers asked the patients to eat half of their calories from an Enteral Nutrition formula, and half from a whole food, predominantly plant-based diet for 6 weeks. 

After 6 weeks, 78.7% of the newly diagnosed patients showed a significant clinical response and 70.6% were in remission. The established disease patients saw similar results. At week 6, 90.4% of the patients were feeling substantially better and 62% were in clinical remission. 

Closing thoughts 

While medication undoubtedly plays a huge role in getting people to remission - and has certainly done so for me - diet can also play a role as part of a holistic view to managing symptoms of Crohn’s or Ulcerative Colitis. Incorporating some fibre, avoiding ultra-processed foods and reducing the amount of meat and dairy can all play a role in developing a healthy, happy gut microbiome and increase the likelihood of maintaining remission. 

For more information about how a plant-based diet might help IBD patients, take a look at the work of plant-forward gastroenterologist Dr Alan Desmond, who provides a wealth of resources on his Instagram page. 

If you are someone who lives with Crohn’s or Ulcerative Colitis you may like to check out my new vegan cookbook, The Plant-Based Crohn’s and Colitis Cookbook, which shares my nutritious, easy-to-digest plant-based recipes created specifically for people suffering with Crohn’s and Colitis, based on my own experiences of living with and cooking for Crohn’s disease.

If you are interested in learning more about the benefits of a plant-based diet check out benefits of tofu and can a plant-based diet help prevent and treat type 2 diabetes?

This article is not intended to be a substitute for medical advice, diagnosis or treatment. If you are a patient with IBD considering a change to your diet, consult a registered dietician for advice.

References

1.  Roberts, C. L. et al., Translocation of Crohn’s disease Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers. Gut 59, 1331-1339 (2010)

2. Brotherton CS, Taylor AG., Dietary fiber information for individuals with Crohn disease: reports of gastrointestinal effects. Gastroenterol Nurs. 2013 Sep-Oct;36(5):320-327

3.  Rauber F, Louzada MLDC, Martinez Steele E, et al, Ultra-processed foods and excessive free sugar intake in the UK: a nationally representative cross-sectional study BMJ Open 2019;9:e027546. doi: 10.1136/bmjopen-2018-027546

4. Nickerson KP, McDonald C (2012) Crohn's Disease-Associated Adherent-Invasive Escherichia coli Adhesion Is Enhanced by Exposure to the Ubiquitous Dietary Polysaccharide Maltodextrin. PLoS ONE 7(12): e52132. https://doi.org/10.1371/journal.pone.0052132

5. Chiba M, Nakane K, Komatsu M., Westernized Diet is the Most Ubiquitous Environmental Factor in Inflammatory Bowel Disease. Perm J. 2019;23:18-107. doi: 10.7812/TPP/18-107. PMID: 30624192; PMCID: PMC6326567.

6.Rotem Sigall-Boneh, RD. Tamar Pfeffer-Gik, RD, Idit Segal, MD, Tsili Zangen, MD, Mona Boaz, RD, PHD, and Arie Levine, MD., 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, Volume 20, Number 8, August 2014.