Macronutrient Intake and Risk of Crohn’s Disease: Systematic Review and Dose–Response Meta-Analysis of Epidemiological Studies

Abstract

Dietary intake is potentially associated with the onset of Crohn’s disease (CD), but evidence from epidemiological studies has remained unclear. This study aimed to evaluate the role of macronutrient intake in the development of CD. A systematic search was conducted in PubMed and Web of Science to identify all relevant studies, and the role of macronutrients in the development of CD was quantitatively assessed by dose–response meta-analysis. Four case-control studies (a total of 311 CD cases and 660 controls) and five prospective cohort studies (238,887 participants and 482 cases) were identified. The pooled relative risks (RR) for per 10 g increment/day were 0.991 (95% confidence interval (CI): 0.978–1.004) for total carbohydrate intake, 1.018 (95% CI: 0.969–1.069) for total fat intake, and 1.029 (95% CI: 0.955–1.109) for total protein intake. Fiber intake was inversely associated with CD risk (RR for per 10 g increment/day: 0.853, 95% CI: 0.762–0.955), but the association was influenced by study design and smoking adjustment. In subtypes, sucrose intake was positively related with CD risk (RR for per 10 g increment/day: 1.088, 95% CI: 1.020–1.160). Non-linear dose–response association was also found between fiber and sucrose intake and CD risk. In conclusion, this meta-analysis suggested a lack of association between total carbohydrate, fat or protein intake and the risk of CD, while high fiber intake might decrease the risk. In subtypes, high sucrose intake might increase the risk of CD.

Environmental Risk Factors for Inflammatory Bowel Diseases: An Umbrella Review of Meta-analyses

“…A total of 145 meta-analytic estimates were retained for the main analysis: 74 (51%) reported effects that were significant at P < .05 and 32 (22%) at P < .001. The putative environmental factors pertained to lifestyles and hygiene (n ¼ 16), 6,18-30 surgeries (n ¼ 2), exposure to drugs (n ¼ 3), [37][38][39][40][41][42] dietary intake and nutrients (n ¼ 22), [43][44][45][46][47][48][49][50][51][52][53][54][55] and microorganisms and vaccinations (n ¼ 28). [56][57][58][59][60][61][62][63][64][65][66][67][68][69] Quality Assessment of Meta-analyses The AMSTAR 2 rating for all studies was determined to be critically low (31 studies, 60%) or low (21 studies, 40%) (Supplementary Table 4).…”

“…43 Sucrose intake also was a risk factor for UC (RR, 1.10; 95% CI, 1.02-1.18; per 10-g increment/day) and CD (RR, 1.09; 95% CI, 1.02-1.16; per 10-g increment/day) with evidence of a dose-response relationship (UC: P ¼ .03; CD: P ¼ .02) ( Figure 3 and Supplementary Tables 1 and 2). 44,45 Alcohol and coffee consumption, however, were not associated with UC ( Figure 3). 43 No evidence of associations between carbohydrate, sugar, protein, or fat intake and either UC or CD were noted in metaanalyses that included high-quality studies (Figure 3 and Supplementary Tables 1 and 2).…”

“…43 No evidence of associations between carbohydrate, sugar, protein, or fat intake and either UC or CD were noted in metaanalyses that included high-quality studies (Figure 3 and Supplementary Tables 1 and 2). [44][45][46] Fruit intake protected against CD (OR, 0.57; 95% CI, 0.44-0.74) and UC (OR, 0.69; 95% CI, 0.49-0.96). 47 Conversely, vegetables intake protected against UC (OR, 0.71; 95% CI, 0.58-0.88) but did not reach significance in CD ( Figure 3 and Supplementary Tables 1 and 2).…”

The role of dietary factors in inflammatory bowel diseases: New perspectives

“…Refined carbohydrates (e.g., sucrose and fructose syrup) are enriched in sugared‐beverages and desserts. Two meta‐analyses found no association between total amount of carbohydrate intake and the risk of IBD, but excessive intake of sucrose was associated with a high risk of both UC and CD . Every 10 g increment in daily intake of sucrose was associated with 10% more likelihood of IBD, of which the possible mechanism was the changes in gut microbiota.…”

“…Two meta-analyses found no association between total amount of carbohydrate intake and the risk of IBD, but excessive intake of sucrose was associated with a high risk of both UC and CD. 24,25 Every 10 g increment in daily intake of sucrose was associated with 10% more likelihood of IBD, of which the possible mechanism was the changes in gut microbiota. Another systematic review confirmed a positive relationship between sugared beverage consumption and the risk of UC, 26 especially for those with a low intake of vegetables for 2 years (between the highest and lowest quintile: incidence rate ratio 1.68, 95% confidence interval…”