Higher Dietary Fibre Intake Is Associated With Lower Risk of Inflammatory Bowel Disease

Prospective Cohort Study

Minzi Deng; Lintao Dan; Shuyu Ye; Xuejie Chen; Tian Fu; Xiaoyan Wang; Jie Chen


Aliment Pharmacol Ther. 2023;58(5):516-525. 

In This Article

Abstract and Introduction


Background: Limited prospective studies that have examined the association of dietary fibre with IBD have provided inconsistent evidence.

Aim: To examine any associations between dietary fibre intake and subsequent incidence of IBD, Crohn's disease (CD) and ulcerative colitis (UC)

Methods: We conducted a prospective cohort study of 470,669 participants from the UK Biobank and estimated dietary fibre intake from a valid food frequency questionnaire at baseline. Incident IBD was ascertained from primary care data and inpatient data. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between dietary fibre intake and the risk of IBD, CD and UC.

Results: During an average follow-up of 12.1 years, we ascertained 1473 incident IBD cases, including 543 cases of CD and 939 cases of UC. Comparing the lowest quintiles, an inverse association was observed between dietary fibre intake and risk of IBD (HR 0.74, 95% CI 0.58–0.93, p = 0.011) and CD (HR 0.48, 95% CI 0.32–0.72, p < 0.001), but not UC (HR 0.92, 95% CI 0.69–1.24, p = 0.595). For specified sources, dietary fibre intake from fruit and bread decreased the risk of CD, while dietary fibre intake from cereal decreased the risk of UC.

Conclusions: Higher consumption of dietary fibre was associated with a lower risk of IBD and CD, but not UC. Our findings support current recommendations to increase the intake of dietary fibre.


The prevalence of inflammatory bowel disease (IBD) has been increasing globally comprising two subtypes, Crohn's disease (CD) and ulcerative colitis (UC).[1] As a crucial modifiable environmental risk factor, the diet has received widespread attention in the aetiopathogenesis of IBD.[2] Among dietary nutrients, dietary fibre has several plausible biological mechanisms that may provide possibilities for the prevention of IBD, such as the production of short-chain fatty acid (SCFA), reduction of circulating inflammation markers, maintenance of the intestinal barrier and regulation of intestinal microbiota.[3] Importantly, specified sources of dietary fibre delivered different health benefits based on solubility, viscosity and fermentability.[4]

Although previously summarised evidence has pointed to an inverse association of dietary fibre intake with CD, not with UC,[5–8] this evidence was evaluated to be of low or critically low quality in the latest umbrella meta-analysis.[9] This is partly because most studies suffer from problems such as recall bias due to case–control designs and small sample sizes and need to be further confirmed by large prospective studies. However, to our knowledge, there is insufficient and conflicting evidence from prospective studies. Only one prospective study conducted in the two US female cohorts (Nurses' Health Studies NHS-I and NHS-II) reported a lower risk of CD for participants with high dietary fibre intake.[10] However, in a related recent study, when these two cohorts were combined with another prospective male cohort (Health Professionals Follow-Up Study), dietary fibre only appeared to reduce the risk of ileocolonic CD, but not the risk of overall CD.[11] Two large prospective studies from Europe reported a null association between dietary fibre and the development of IBD, raising concerns about the possibility of dietary fibre to prevent the development of IBD.[12,13]

Therefore, to answer the questions (1) whether the inverse association between dietary fibre and IBD onset is stable and (2) the role of dietary fibre from different food sources on IBD onset, we systematically conducted a prospective cohort study in the UK Biobank to explore the associations between dietary fibre intake from fruit, vegetable, bread, and cereal sources and risk of IBD and IBD subtypes.