C Pennaneach et al. Clin Gastroenterol Hepatol 2026; 24: 2584-2594. High Prevalence of Disorders of Irritable Bowel Syndrome and Functional Dyspepsia in Night Shift Workers: A Cross-Sectional Study in Australia and the United Kingdom
Background: “Approximately 15% to 25% of the global workforce operates outside conventional daytime hours.1–3 These schedules typically occur between 6:00 pm and 6:00 am4 and typically take 2 forms: fixed night shifts (consistent night-time work) or rotating (alternating between day, afternoon and night). This distinction is physiologically significant; although fixed night workers may partially adapt to their schedule over time, rotating shift workers face continuous circadian disruption due to frequently changing schedules, preventing biological adaptation.5 This circadian misalignment creates a particularly vulnerable subset of workers and is associated with increased risk of chronic conditions, including cardiovascular disease,6 type 2 diabetes,7 and gastrointestinal (GI) disturbances.8 These adverse outcomes primarily stem from disruption of central and peripheral biological clocks.9“
Methods: This was a cross-sectional study of night shift workers (≥8 shifts/mo between 11 pm and 3 am) in Australia and the United Kingdom from March to July 2024. Participants (n=392) completed validated questionnaires including Rome IV criteria for IBS and FD. Fixed night shift workers constituted 54.1% of the sample, whereas 45.9% worked rotating shifts.
Key findings:
- 21.3% met Rome IV criteria for IBS, 30.4% for FD, and 24.5% for both conditions. The rates of IBS and FD in this cohort was substantially more than “general estimates of 4.1%” general population estimates (4.1% for IBS and 7.2% for FD),10“
- Most participants (59.9%) reported night shifts negatively affected their GI symptoms, and 16.3% considered changing jobs due to symptoms.
The authors discuss the many ways that circadian disruption can adversely affect the GI tract. In addition, night shift workers are more likely to adopt irregular dietary habits which could be a contributing factor as well.
My take: This study shows that night shift work is associated with high rates of disorders of gut-brain interaction (DGBI) likely due to disturbance in circadian rhythms. It is in agreement with other studies showing that disturbed sleep worsens IBS symptoms (A Patel et al. Aliment Pharmacol Ther. 2016; 44(3):246–258).
Related blog posts:
- Treatment Guidelines for Pediatric Irritable Bowel Syndrome
- Dr. Carlo DiLorenzo: Advice for Managing DGBIs (Part 2) “Improving Physical activity, Diet and Sleep Often Helps DGBI symptoms”
- NPR: Understanding “Sleep Munchies”
- More on Staying Up All Night
- Negative Study: Nortriptyline for Functional Dyspepsia
- Functional Dyspepsia in Clinical Practice
- Is Infantile Colic a Biorhythm Disorder?
- Rome V: Lower GI Tract and Biliary Disorders of Gut-Brain Interaction in Pediatrics (Part 1)

This was a good hike with serpentine canyon walls and a long waterfall at the end






















