Soluble and Osmotic Fibre (SOLOS) Diet for Constipation

NCT07388589 | Not Yet Recruiting

• 1 other identifier: RECAS-0723-IRB
• Study Type: observational
• Target: 180
• Locations: 1 country
• Sites: 1

Brief Summary

This research aims to study the dual effectiveness of incorporating soluble fibre and osmotic carbohydrates (SOLOS), with or without restricting fructans and GOS, and present novel findings in managing GI symptoms in patients with functional bowel disorders with constipation. These findings may also support researchers and clinicians in shaping new dietary approaches in the management of general constipation symptoms.

Conditions

Constipation-predominant Irritable Bowel Syndrome (IBS-C); Constipation; Constipation - Functional; Constipation Chronic Idiopathic; Constipation Predominant Irritable Bowel Syndrome; Constipation, Signs and Symptoms, Digestive; Constipation-predominant IBS (IBS-C); Constipation-predominant Irritable Bowel Syndrome; Diet Therapy; Diet Modification; Diet, Food and Nutrition; Dietary and Nutritional Therapies; Dietary Fiber; Dietary Fibers

Keywords

Constipation; Functional constipation; Constipation-predominant irritable bowel syndrome (IBS-C); Soluble fiber; osmotic sugar

Outcome Measures

Primary Outcomes (4)

• Stool frequency

  Frequency of stool output per week

  January 2021 to December 2025

• Stool form

  Bristol Stool Form Scale

  January 2021 to December 2025

• Gastrointestinal Symptom Frequency

  Frequency of gastrointestinal symptom in a week, recorded as number of days out of 7 the symptom occurred over the past week.

  January 2021 to December 2025

• Gastrointestinal Symptom Severity

  Severity of symptoms in a week scored using Gastrointestinal Symptom Rating Scale (GSRS). Scores range from 0 (absent) to 3 (severe).

  January 2021 to December 2025

Study Arms (2)

Patients with Functional Constipation

Other: Diet

Patients with IBS-C or SIBO-C

Other: Diet

Interventions

Diet OTHER

Dietary advice combining increased intake of dietary sources of soluble fibres and osmotic sugars in improving constipation symptoms.

Also known as: soluble fibre and osmotic carbohydrates diet, soluble fibre and osmotic carbohydrates (SOLOS) diet, SOLOS diet

Patients with Functional Constipation; Patients with IBS-C or SIBO-C

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult patients (18-70 years old) with functional bowel disorders with constipation from the UK, seen by a specialist dietitian (Principal Investigator)

You may qualify if:

• Presented with symptoms of FC, IBS-C, or SIBO-C
• Were aged 18 to 70 years old. (Research focus is on adult patients, excluding older adults and children)
• Date of baseline (first) and follow-up appointments ranged from January 2021 to December 2025
• Did not attend follow-up appointments (Data would be treated as "intention to treat" and data points were carried forward for conservative analysis).

You may not qualify if:

• Had no history of constipation-related symptoms (Does not relate to research question's population or outcome)
• Started treatment before January 2021
• Were not due for follow-up before the end of December 2025
• Symptom and stool data inadequately recorded

Sponsors & Collaborators

• Singapore Institute of Technology: lead

Study Sites (1)

Singapore Institute of Technology

Singapore, Singapore, 828608, Singapore

Location

MeSH Terms

Conditions

Constipation

Interventions

Diet

Condition Hierarchy (Ancestors)

Signs and Symptoms, Digestive; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Study Officials

• Bridgette J Wilson, Dr

  Singapore Institute of Technology

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Bridgette J Wilson, Dr

CONTACT

+65 82629995; bridgette.wilson@singaporetech.edu.sg

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: January 28, 2026
• First Posted: February 5, 2026
• Study Start: February 2, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: February 6, 2026

Record last verified: 2026-02

Locations

SG (1)