Effects of an Intermittent Reduced Calorie Diet on Crohn's Disease

The purpose of this study is to see how an Intermittent Calorie Reduced Diet (IRCD) that mimics fasting (also known as a fasting mimicking diet, FMD) effects inflammation in patients with mild to moderate Crohn's disease (CD). The diet may allow users to receive the benefits of fasting while also being able to enjoy food (the ingredients of which are GRAS (generally recognized as safe) by the Food and Drug Administration (FDA). Research on dietary interventions and CD are very limited. Diets that mimick fasting have been studied with support of the National Institute of Health and published in leading journals. This research investigates whether markers of inflammation decrease and/or quality of life increases after five-day periods of the IRCD, and may provide rationale for its use to treat CD.

Study Overview

• Status: Completed
• Conditions: Inflammatory Bowel Diseases; Diet Modification; Crohn Disease
• Intervention / Treatment: Other: Intermittent Reduced Calorie Diet (IRCD)

Detailed Description

As above

• Study Type: Interventional
• Enrollment (Actual): 86
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Palo Alto, California, United States, 94305
      • Stanford University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Mild to moderate Crohn's disease (CDAI score 151-450)
• Between the ages of 18-70 (inclusive)

Exclusion Criteria:

• Women who are pregnant, nursing or expect to be pregnant
• Individuals allergic to nuts
• Individuals with a body mass index (BMI) lower than 18
• Individuals diagnosed with a serious medical condition (unless approved in writing by a physician)
• Individuals who have been severely weakened by a disease or medical procedure
• Individuals who are taking medication which may not be safely consumed with a calorie restricted diet
• Individuals with diabetes who are taking anti-diabetic drugs associated with risk of hypoglycemia
• Individuals with more than mild-moderate cardiovascular disease or life-threatening cancer (as determined by patient's physician) unless approved by a physician
• Individuals with history of severe cardiac disease (particularly uncompensated congestive heart failure NYHA grade 2 or more or LVEF < 40%)
• Individuals with a history of syncope
• Individuals with dietary needs incompatible with the IRCD meal plan
• Individuals with liver or kidney disorders that may be affected by very low glucose and protein content of the diet
• Patients on a calorie restricted diet will also be excluded
• Patients with relevant prior gastrointestinal surgery and consequences such as short bowel syndrome, ostomy of small or large intestine,total colectomy, proctocolectomy, ileoanal pouch will be excluded (not excluded are patients with resection of terminal ileum, resection of short strictures of the small intestine, hemicolectomy).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention Arm; Three cycles of a 5-day Intermittent Reduced Calorie Diet	Other: Intermittent Reduced Calorie Diet (IRCD); Three cycles of a 5-day Intermittent Reduced Calorie Diet over three months.
No Intervention: Control Arm; Regular Diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants with Clinical response as per CDAI (70 points)	Defined as reduction of the CDAI of at least 70 points or achieving a CDAI score ≤ 150.	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants with Clinical remission as per CDAI	Defined as a CDAI score ≤ 150.	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Number of Participants with Clinical response as per CDAI (100 points)	Defined as reduction of the CDAI of at least 100 points or achieving a CDAI score ≤ 150.	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Number of Participants with Clinical response as per CDAI (70 points)	Defined as reduction of the CDAI of at least 70 points or achieving a CDAI score ≤ 150.	Assessed 3 months after 3rd cycle. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Number of Participants with Clinical remission as per Patient Reported Outcome (PRO) score	Defined as average worst daily abdominal pain score of ≤ 1 (using a 4-point scale, 0-3) and a loose/watery stool (Bristol Type 6 or 7) frequency score of <=3.	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Patient global assessment	"Do you believe you are in remission from your CD symptoms?" (Yes/No). No scale.	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Effect of IRCD on endoscopic outcomes	Changes in Simplified Endoscopic Activity Score for Crohn's Disease (SES-CD). SES-CD scores range from 0 to 56 and higher scores indicate more severe disease.	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Effect of IRCD on patient quality of life: Short Inflammatory Bowel Disease questionnaire (SIBDQ)	Changes in SIBDQ. Response to each of the questions is graded from 1 to 7 (1 being the worst situation and 7 the best).	Assessed within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Change in C-reactive protein (CRP) at baseline versus after 3rd cycle of IRCD (or control at corresponding time point) in both IRCD and control group.	Change of the inflammatory marker CRP.	Baseline versus within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Change in Erythrocyte Sedimentation Rate (ESR) at baseline versus after 3rd cycle of IRCD (or control at corresponding time point) in both IRCD and control group.	Change of the inflammatory marker ESR.	Baseline versus within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Change in fecal calprotectin at baseline versus after 3rd cycle of IRCD (or control at corresponding time point) in both IRCD and control group.	Change of the inflammatory marker fecal calprotectin.	Baseline versus within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants with Clinical remission as per CDAI	Defined as a CDAI score ≤ 150.	Assessed 3 months after 3rd cycle. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Number of Participants with Clinical response as per CDAI (100 points)	Defined as reduction of the CDAI of at least 100 points or achieving a CDAI score ≤ 150.	Assessed 3 months after 3rd cycle. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Effect of IRCD on patient quality of life: Short Inflammatory Bowel Disease questionnaire (SIBDQ)	Changes in SIBDQ. Response to each of the questions is graded from 1 to 7 (1 being the worst situation and 7 the best).	Assessed 3 months after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Changes in cytokines/chemokines and immune cell profiles	Using flow cytometry and mass cytometry (CyTOF)	At baseline versus within 6 days after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Changes in gut metabolites (including short-chain fatty acid and bile acid profiles) and microbiome profiles (using 16S rRNA/shotgun metagenomics)	Gut metabolites include short-chain fatty acid and bile acid profiles.	At baseline versus within 6 days after 3rd cycle of IRCD and 3 months after 3rd cycle. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Changes in clinical markers of disease activity	Clinical markers of disease activity are CRP, ESR, and fecal calprotectin.	At baseline versus 3 months after 3rd cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.
Changes in clinical markers of disease activity	Clinical markers of disease activity are CRP, ESR, and fecal calprotectin.	At baseline versus within 6 days after 1st cycle of IRCD. 1 cycle of IRCD lasts 5 days and is administered once a month, followed by regular diet for the rest of the month.

Collaborators and Investigators

• Sponsor: Stanford University
• Investigators: Principal Investigator: Sidhartha R Sinha, MD, Stanford University

Study record dates

Study Major Dates

• Study Start (Actual): December 18, 2019
• Primary Completion (Actual): March 12, 2024
• Study Completion (Actual): May 6, 2024

Study Registration Dates

• First Submitted: October 25, 2019
• First Submitted That Met QC Criteria: October 29, 2019
• First Posted (Actual): November 1, 2019

Study Record Updates

• Last Update Posted (Actual): April 17, 2025
• Last Update Submitted That Met QC Criteria: April 14, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Keywords: Diet; IBD; intermittent fasting; Crohn's disease; CD; Fasting; FMD; Intermittent Reduced Calorie Diet
• Additional Relevant MeSH Terms: Intestinal Diseases; Digestive System Diseases; Gastrointestinal Diseases; Gastroenteritis; Crohn Disease; Inflammatory Bowel Diseases
• Other Study ID Numbers: IRB 53161

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No