High diet quality in early life may help prevent IBD later

A high diet quality characterized by increased intake of fish and vegetables and limited consumption of sugary drinks at 1 year of age appears to offer protection against subsequent inflammatory bowel disease (IBD), as reported in a study.

Data from two Scandinavian birth cohorts showed that compared with low diet quality, medium and high diet quality at age 1 year reduced the risk of developing IBD during childhood and adolescence by 25 percent (pooled adjusted hazard ratio [aHR], 0.75, 95 percent confidence interval [CI], 0.58–0.98 and pooled aHR, 0.75, 95 percent CI, 0.56–1.00, respectively). [Gut 2024;doi:10.1136/gutjnl-2023-330971]

Diet quality was measured using a modified version of the Health Eating Index (HEI), wherein a high modified HEI score equated to a higher intake of fruits and vegetables, dairy products, and fish, as well as a lower intake of meat, sweets, snacks, and sweet drinks.

Looking at specific food groups, significant findings emerged for intakes of fish, vegetables, and sugar-sweetened beverages. For fish, a high versus low intake was associated with a reduced risk of IBD overall (pooled aHR, 0.70, 95 percent CI, 0.49–1.00) and ulcerative colitis (UC) specifically (pooled aHR, 0.46, 95 percent CI, 0.21–0.99). For vegetables, medium and high versus low intake also conferred a protective effect on IBD risk (pooled aHR, 0.66, 95 percent CI, 0.49–0.89 and pooled aHR, 0.72, 95 percent CI, 0.55–0.95, respectively).

Conversely, some intake of sugar-sweetened beverages carried a heightened risk of IBD compared with no intake (pooled aHR, 1.42, 95 percent CI, 1.05–1.90).

No association was found between diet quality at 3 years of age and subsequent IBD risk.

The analysis included 81,280 participants who were followed from birth through childhood and adolescence. Of these, 307 received an IBD diagnosis during 1,304,433 person-years of follow-up.

Gut health

“Although we cannot rule out other explanations, the new findings are consistent with the hypothesis that diet early in life, possibly mediated by changes in the gut microbiome, can affect the risk of developing IBD,” according to first study author Annie Guo, a dietician and postgraduate student in paediatrics at the University of Gothenburg in Gothenburg, Sweden.

Several studies support the link between gut health and diet. A retrospective Italian study showed that children aged 2–17 years with UC had significantly poorer adherence to a Mediterranean-style diet compared with their healthy peer. Likewise, in a prospective cohort study of adults, high adherence to a modified Mediterranean diet was associated with a lower risk of Crohn’s disease (CD) but not UC. Increased consumption of fish in children and adolescents has also been linked to a reduced risk of CD.  [J Pediatr Gastroenterol Nutr 2017;64:569-574; Gut 2020;69:1637-1644; Am J Gastroenterol 2007;102:2016-2025]

“The content of polyunsaturated fatty acids (PUFAs) or vitamin D in fish may be of special importance for IBD, as adult studies have observed an inverse association between a high intake of PUFAs and later UC and a high intake of vitamin D and CD,” Guo noted. [Gut 2014;63:776-984; Gastroenterology 2012;142:482-489]

She added that the influence of diet on IBD risk may be age-dependent, in light of the finding that dietary habits at 3 years of age were not associated with later IBD risk.

“The early-life gut microbiome undergoes significant changes until it converges to a stabilized, more adult microbiome after age 2 and 3 years. Since the gut microbiome seems to develop very early in life, diet at 1 year rather than at 3 years may have a stronger impact on the microbiome,” Guo explained. [Nature 2018;562:583-588; Front Pediatr 2022;10:815885]

“Regrettably, the lack of microbiome data prevented the study of whether changes in microbial composition mediated the IBD risk related to early-life diet,” she acknowledged.