https://orcid.org/0000-0001-6382-0047
To the Editor,
We read Limketkai et al’s article1 with great interest. Dietary patterns in inflammatory bowel disease (IBD) were determined by unsupervised machine learning algorithms. Plant-based diets (PBDs) (PB1 and PB2) were associated with lower odds of active symptoms. PB2, more consumption of the plant diet and less consumption of the animal diet than PB1, was more effective than PB1. The remission rate in Crohn’s disease (CD) was 50.0% with PB2, while it was 14.8% to 27.0% with the other 4 patterns (2 patterns of Western diets, a balanced diet, and PB1). Even with PB2, more animal products were consumed more than with a (semi-)vegetarian diet, judging from the radar plot of dietary patterns and relative consumption of different food items. More than a half of patients with CD were medicated with biologics, corticosteroids, or immunomodulators; therefore, the remission was interpreted as being the result of PB2 and medication. Nevertheless, the article showed the superiority of PBDs over Western diets or a balanced diet.1
We would like to add our observation. We assert that IBD occurs in susceptible individuals mainly as a result of our omnivorous (Westernized) diet.2 Therefore, we developed and began to provide a PBD, a lacto-ovo-semi-vegetarian diet, to IBD patients in 2003 to encounter the omnivorous diet. Infliximab together with a PBD was indicated as first-line therapy for all patients with newly developed CD3 because the majority of CD patients are destined for a disabling course.4 Our modality, infliximab and PBD as first-line (IPF) therapy, broke the barrier of primary nonresponders to biologics (around 30%) and created a new relapse-free course in CD (Figure 1).5 The remission rate in CD at 6 weeks after IPF therapy was 96% (n = 44 of 46).3 Freedom from relapse at 10 years after IPF therapy in CD was achieved in nearly a half of patients (52%) without the aforementioned medications.5 We assume that absence of primary nonresponders in our study is due to sufficient butyrate fermented from dietary fiber contained in PBD.6
Graphic of clinical course in Crohn’s disease. Solberg et al11 presented 4 graphic clinical courses of Crohn’s disease: curve 1 (decrease in the severity of bowel symptoms), curve 2 (increase in the severity of bowel symptoms), curve 3 (chronic continuous bowel symptoms), and curve 4 (chronic relapsing bowel symptoms). Reprinted with permission from Solberg et al.11 A relapse-free course was attained in nearly a half of Crohn’s disease patients with infliximab and plant-based diet as first-line therapy.5 Reprinted with permission from Chiba et al.5.
Data from Japan showed an increased incidence of IBD in association with dietary Westernization during and after economic growth.7 Current global consumption consists of an excess of unhealthy foods and a shortage of healthy foods.8 Basic research has revealed the interplay between diet and microbiota and its metabolite and health or disease and concluded that a Westernized diet tends to be proinflammatory, while a PBD tends to be anti-inflammatory.9,10 Therefore, the current diet is problematic and should be changed to a suitable one in IBD. We believe that a plant-based diet is the right one for IBD.
Conflicts of Interest
None.
Funding
None.
