Feb 14, 2026
3 min read
Can changing the timing of meals improve symptoms of Crohn's disease?Research shows that mealtime alone can help—not necessarily a change in diet.
In brief
- In adults with Crohn's disease who ate only during an 8-hour period (fasting 16 hours a day), stool frequency was reduced by 40% and stomach pain was halved.
- Participants don't change what they eat or count calories, they just eat regular meals over short periods of time
- The eating schedule reduced the risk of abdominal fat, while the control group did
- All participants were taking pain relievers and medications, so this approach helps control symptoms
Adults with Crohn's disease lose dangerous belly fat and reduce significant symptoms when they eat, not what they eat, according to a Canadian study.Participants ate their normal meals and did not count calories.They compress all their food into the window for eight hours every day, fasting for the remaining 16 hours six days a week.
About 40% of people with Crohn's disease are overweight or obese, and excess body fat (especially that which surrounds internal organs) can make the disease worse.This visceral fat pumps out inflammatory chemicals that trigger more severe disease activity, reduce the effectiveness of medications, and increase the risk of needing surgery.Despite these risks, doctors rarely recommend special diet plans to address weight and inflammation in Crohn's patients.
A study published in Gastroenterology measured calorie intake and diet quality over a 12-week trial and found no difference between the fasting group and controls.People don't eat less or eat healthier, they eat the same foods for a short period of time.However, their bodies responded dramatically.During a 16-hour fast, the body taps into a ready supply of glucose and breaks down stored fat for fuel.begins, which can trigger a cascade of anti-inflammatory effects.
How the meal schedule works
Researchers at the University of Calgary and the University of British Columbia enrolled 35 adults with Crohn's disease who were obese and had silent but untreated disease.Half followed the 16:8 fasting schedule: eating all of their food within an eight-hour window, such as between 10 a.m. and 6 p.m.The other half continued to eat according to their daily schedule with no time limit.
Participants in the fasting group maintained their usual diet.A registered dietitian showed up at the beginning and around the fourth week and remained available throughout the study.Both groups remained on their usual Crohn's disease medications.
Adherence is very high, about 95%.Participants entered daily eating windows and were detained by researchers every two weeks.At the beginning and end, the researchers measured body weight, body composition using special scans, blood markers, stool samples, and disease activity.
The changes made sense
Body mass index decreased significantly (by almost a full point) in the fasting group, while the control group's BMI actually increased slightly.Even more remarkable is what happened to visceral fat.Participants following the diet lost significant amounts of this dangerous visceral fat, while the control group gained it.
Clinical symptoms improved significantly.Stool frequency decreased by 40% and abdominal discomfort decreased by 50%.Disease Severity Scores decreased by 2 points in the fasting group, compared to only half a point in controls.For patients trying to avoid flare-ups, these changes can make a real difference in everyday life.
Blood tests showed major changes in obesity-related hormones.Leptin, a hormone produced by fat cells that promotes inflammation, was dramatically reduced.Two other proteins secreted by adipose tissue were also significantly reduced.Scientists believe that these hormones link excess body fat to immune system problems, so reducing them may help calm the inflammatory process in Crohn's disease.
Participants who lost more than one BMI unit showed increases in pro-inflammatory and anti-inflammatory immune molecules.The researchers believe that this mixed immune signal may reflect the timing of immune adaptation, but this remains speculative.
Gut bacteria researchers show shift
In exploratory analyses, stool samples showed different gut bacteria in the fasting group.Certain bacteria are known to produce beneficial compounds called short-chain fatty acids that multiply.These compounds help maintain the intestinal barrier and have an anti-inflammatory effect.
In Crohn's disease, the leaky intestinal barrier allows bacteria and food particles to escape the gut and trigger an immune response.Bacteria that produce these protective compounds can help repair this barrier.Although the findings did not reach statistical significance after calculating several comparisons, they are in line with other studies showing that fasting can promote beneficial bacteria.
Why are hours as important as calories?
Other studies have shown that prolonged fasting can affect the body's daily internal rhythm: a natural cycle that facilitates when gut bacteria are active and when immune cells patrol the gut lining.
By integrating food intake into a defined window, this eating pattern can restore normal daily cycles of bowel function.In this study, traditional markers of active intestinal inflammation remained stable in both groups, suggesting that the improvements reflected better symptom control and metabolic health rather than healing of existing damage.
What this means for treatment
This meal plan for overweight people with Crohn's disease offers a simple approach that doesn't require special foods, supplements, or complicated meal planning.Participants stopped eating in the early evening and skipped breakfast.
Reducing visceral fat has benefits beyond symptom control.This type of fat is associated with worse reactions to biologic drugs, the expensive IV or injection medication that most Crohn's patients rely on to maintain remission.If the diet can reduce this problem fat, the drugs will work better.
This was a small study of 35 participants for 12 weeks, so larger and longer trials are needed to confirm these results and find out if people can maintain this diet for years.All participants were in remission at the beginning, so it is not clear whether this method can help people with active disease.This study also did not have a calorie-matched control group, making it difficult to know whether the benefits are from the diet itself or moderate weight loss.
However, doctors who treat inflammatory bowel disease often focus on medication management, sometimes neglecting lifestyle factors that affect the development of the disease.These findings suggest that metabolic health and physical activity are closely related, and that simple behavioral changes can complement medical treatment.Patients don't have to stop their medications, but they can consider adding them to the prescribed treatment.
Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.Always seek the advice of your doctor or other qualified health care provider with any questions you may have about a medical condition.Do not ignore or delay in seeking professional medical advice because of anything you have read in this article.
This randomized controlled trial enrolled 35 participants (20 in the fasting group, 15 controls) over 12 weeks.The small sample size and short duration limit the ability to draw broad conclusions.The study lacked a calorie-matched control group, making it difficult to quantify the effects of meal timing on modest weight loss.All participants were in clinical remission and on stable medication, so the results may not apply to people with active disease.Participants with serotypes were excluded from the study.Gut bacteria findings were exploratory and statistical improvements did not survive multiple tests.Conventional inflammatory markers (C-reactive protein and faecal calprotectin) did not change significantly.
Funding and Disclosure
This work was funded by Litwin IBD Pioneers from the Crohn's and Colitis Foundation (ID: 879104) and Imagine Network (University of Calgary).Natasha Haskey is supported by a TRIANGLE (Training a Next Generation of Gastroenterology and LivEr Researchers) Postdoctoral Fellowship and a Michael Smith Health Research BC Health Professional Investigator Award.The authors disclose no conflicts of interest.
Authors: Natasha Haskey, PhD, RD (Department of Biology, University of British Columbia, Kelowna, BC, Canada); Jiayu Ye, PhD (Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Palo Alto, CA); (Department of Medicine, Cumming Faculty of Medicine, University of Calgary, Calgary, AB, Canada); Raylene A. Reimer, PhD, RD (Department of Exercise Function, University of Calgary, Calgary, AB, Canada); Maitreyi Raman, MD, MSc, FRCPC(Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada) |Journal: Gastroenterology (2025, ing press) |Title: “Watesan Diet Time Reduces Crew Mass Index, Visceral Adiposity, Systemic Inflammation, and Clinical Disaster Activity in Adult Crohn’s Nursing: A Randomized Controlled Study” |DOI: https://doi.org/10.1053/j.gastro.2025.11.008|Clinical Trial Registration: ClinicalTrials.gov, Number NCT05230160 |Pariten said follow-up was conducted from May 2023 to January 2024 at outpatient clinics in Calgary, Alberta, and Kelowna, British Columbia, Canada.It received ethics approval from the University of British Columbia (H22-02645) and the University of Calgary (REB21-1539).Canty reported.
