Plant-based Diets for Inflammatory Bowel Disease: What Is the Evidence?

Inflammatory bowel disease is a chronic incurable condition that carries a high morbidity burden for patients. Plant-based diets have emerged as a potentially safe and effective treatment strategy for this condition. However, no attempt has been made to summarize the literature in this field. In this review, we aim to define variants of plant-based diets that have been studied, evaluate their findings, and identify knowledge gaps that warrant further investigation.

A literature search was conducted on MEDLINE and Embase.

Twenty-three studies with 2304 participants were included in this review. Eleven studies (48%) were case reports and 8 (35%) were single-arm trials. Semivegetarian diets were the most commonly studied plant-based diet (n = 14, 61%). Most studies reported that plant-based diets were safe and effective in managing inflammatory bowel disease. However, significant limitations restrict the quality and interpretability of these findings, including a paucity of controlled data, small sample sizes, and inconsistent reporting of dietary adherence.

Although initial findings appear promising, it remains unclear whether plant-based diets are an effective adjunct or sole therapy for managing inflammatory bowel disease. Future investigators should aim to conduct methodologically rigorous interventional trials with appropriate control data and consistent and meaningful outcome reporting.