Should patients with IBD avoid ultra-processed foods?

Evidence for the effect of UPFs in IBD is limited to observational epidemiological studies. There have been no intervention studies on UPFs in patients with IBD. While whole-food diets currently used by patients in an attempt to reduce disease activity – including the Specific Carbohydrate Diet [8], the Crohn’s Disease Exclusion Diet [9], the Ulcerative Colitis Exclusion Diet [10] and the Mediterranean diet [11] – may differ in their dietary rules, they all minimise the dietary content of most UPFs. However, evidence from dietary studies alone is insufficient to advise patients to limit UPFs. 

UPFs are a challenging area of nutrition to study. There are many separate components in UPFs that could be contributing to disease. For example, UPFs often contain artificial additives, but they are also higher in sugar and fat and lower in fibre and certain micronutrients compared to non-processed foods [12]. Individual components of UPFs, such as artificial sweeteners, emulsifiers or food colours, have been shown in preclinical studies to decrease bacterial diversity, disrupt intestinal barrier function and increase intestinal inflammation [13]. Human intervention studies isolating these dietary components and investigating their impact on IBD disease course are underway. Interestingly, exclusive enteral nutrition formulations used to downstage inflammation in CD contain a multitude of food additives; this challenges the notion that UPFs are detrimental in IBD [14]. 

What should I advise patients on ultra-processed foods?

• To reduce the risk of IBD development, children should be provided with balanced diets that limit the intake of UPFs [15].
• There is insufficient evidence from human studies to suggest that patients with existing IBD should avoid the whole food category of UPFs to manage their disease [16].
• However, patients with diets high in UPFs are likely to have nutritionally unbalanced diets. These patients should be advised to bring their diet into line with the healthy eating guidance that applies to the general population for overall health.
• Patients on restrictive diets/at risk of malnutrition/with a history of disordered eating will be at further nutritional risk if advised to avoid UPFs. Indeed, UPFs may have a role in the diet by assisting patients with weight gain and promoting nutritional adequacy.
• Many patients have a holistic interest in managing their disease through diet. These patients can be directed towards other existing evidence-based dietary strategies, which should be adopted under the supervision of a dietitian.
  

References

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