OAT-GUT-BRAIN: Effects of Oats and Rice on Comprehensive Health of Metabolically Challenged Individuals

NCT05526092 | Active Not Recruiting

• 1 other identifier: OGB
• Study Type: interventional
• Target: 72
• Locations: 1 country
• Sites: 2

Brief Summary

The overall objective of this research entity is to reveal the comprehensive health impact of oats in metabolically challenged individuals in a 6-week intervention, compared to that of rice. This is achieved by investigation of the lipids, short-chain fatty acids, inflammation markers and antioxidant status from plasma, fecal microbiome, and plasma metabolome. Additionally the effect of the 6-week diet on postprandial glycemia and postprandial satiety and vitality are investigated.

Conditions

High Blood Pressure; Overweight and Obesity; High Cholesterol/Hyperlipidemia

Outcome Measures

Primary Outcomes (2)

• Changes from Baseline in Serum Total Cholesterol

  Serum total cholesterol will be measured from fasting blood samples at the baseline (week 0) and after 6 week of the dietary intervention (week 6).

  Week 0 and Week 6

• Changes from Baseline in Interleukin-10

  Interleukin-10 is measured from fasting plasma samples at the baseline (week 0) and after the 6-week diet intervention (week 6). It will be analysed as part of the Olink Target 48 Cytokine Panel (Olink Proteomics, Uppsala, Sweden) that provides absolute quantities for 45 different proteins, such as interleukins, interferons, chemokines and growth factors that are related to inflammation.

  Week 0 and Week 6

Secondary Outcomes (19)

• Changes from Baseline in Blood Lipids

  Week 0 and Week 6

• Changes from Baseline in Glucose Metabolism

  Week 0 and Week 6

• Changes in Postprandial Glucose metabolism

  0, 15, 30, 45, 60, 90, 120, 180 minutes after the study meal at week 0 and week 6

• Changes from Baseline in Inflammation markers

  Week 0 and Week 6

• Changes from Baseline in Plasma metabolome

  Week 0 and Week 6

Other Outcomes (7)

• Changes in postprandial status of inflammation markers

  0, 15, 30, 45, 60, 90, 120, 180 minutes after the study meal at week 0 and week 6

• Changes postprandial status of Plasma Short-Chain Fatty Acids

  0, 90, 180 minutes after the study meal at week 0 and week 6

• Changes in postprandial status of Plasma metabolome

  0, 15, 30, 45, 60, 90, 120, 180 minutes after the study meal at week 0 and week 6

Study Arms (4)

Oat-rich and low-gluten diet with oat-rich meal test

EXPERIMENTAL

Participants will consume oats as the main cereal in their diet and follow low-gluten diet for 6 weeks. In postprandial meal test, they will be served an oat-rich breakfast.

Other: Dietary intervention; Other: Postprandial meal test

Rice-rich low-gluten diet with oat-rich meal test

ACTIVE COMPARATOR

Participants will consume rice as the main cereal in their diet and follow low-gluten diet for 6 weeks. In postprandial meal test, they will be served an oat-rich breakfast.

Other: Dietary intervention; Other: Postprandial meal test

Oat-rich low-gluten diet with rice-rich meal test

EXPERIMENTAL

Participants will consume oats as the main cereal in their diet and follow low-gluten diet for 6 weeks. In postprandial meal test, they will be served a rice-rich breakfast.

Other: Dietary intervention; Other: Postprandial meal test

Rice-rich low-gluten diet with rice-rich meal test

ACTIVE COMPARATOR

Participants will consume rice as the main cereal in their diet and follow low-gluten diet for 6 weeks. In postprandial meal test, they will be served a rice-rich breakfast.

Other: Dietary intervention; Other: Postprandial meal test

Interventions

Dietary intervention OTHER

Changes in dietary intake, metabolism, fecal microbiome, vitality and perceived health after a 6-week consumption of oat or rice-rich low-gluten diet.

Oat-rich and low-gluten diet with oat-rich meal test; Oat-rich low-gluten diet with rice-rich meal test; Rice-rich low-gluten diet with oat-rich meal test; Rice-rich low-gluten diet with rice-rich meal test

Postprandial meal test OTHER

Postprandial changes after the 6-week consumption of either oat or rice-rich low-gluten diet, including blood markers, microbiome, satiety, recovery and vitality.

Oat-rich and low-gluten diet with oat-rich meal test; Oat-rich low-gluten diet with rice-rich meal test; Rice-rich low-gluten diet with oat-rich meal test; Rice-rich low-gluten diet with rice-rich meal test

Eligibility Criteria

• Age: 30 Years - 68 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Commits to follow the instructed low-gluten diet for 6 weeks
• years of age
• BMI \> 25 kg/m\^2
• High cholesterol (without medication) characterized as total cholesterol \> 5 mmol/l, AND either LDL \> 3 mmol/l OR HDL (men/women) \< 1.0/1.2 mmol/l AND/OR Hypertension (systolic \> 140 mmHg or diastolic \> 90 mmHg).

You may not qualify if:

• Regular medication that can affect the research outcomes (balanced medication for hypertension, hypo-/hyperthyroidism, hormone replacement therapy, and inhaled medicines allowed)
• Pregnancy or lactation
• Heavy smoking
• Recent course of antibiotics (less than 3 months prior to the study)

Sponsors & Collaborators

• University of Turku: lead
• University of Eastern Finland: collaborator

Study Sites (2)

Food Sciences, Department of Life Technologies, University of Turku

Turku, Turku, 20500, Finland

Location

Institute of Public Health and Clinical Nutrition, University of Eastern Finland

Kuopio, 70211, Finland

Location

Related Publications (1)

• Mannila E, Nuotio P, Kuosmanen A, De Storvik S, Karlund A, Jukkara A, Tauriainen MM, Narvainen J, Kolehmainen M, Linderborg KM. Comparison of Low-Gluten Diets Rich in Oats or Rice-A 6-Week Randomized Clinical Trial With Metabolically Challenged Volunteers. Mol Nutr Food Res. 2025 Jun;69(12):e70076. doi: 10.1002/mnfr.70076. Epub 2025 May 7.

  PMID: 40331457 RESULT

Related Links

• Home page of the study, in Finnish

MeSH Terms

Conditions

Hypercholesterolemia; Hyperlipidemias; Hypertension; Overweight; Obesity

Interventions

Diet Therapy

Condition Hierarchy (Ancestors)

Dyslipidemias; Lipid Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Vascular Diseases; Cardiovascular Diseases; Overnutrition; Nutrition Disorders; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Nutrition Therapy; Therapeutics

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: August 26, 2022
• First Posted: September 2, 2022
• Study Start: September 12, 2022
• Primary Completion: December 31, 2023
• Study Completion (Estimated): December 1, 2027
• Last Updated: April 13, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF, ANALYTIC CODE
• Time Frame: IPD will be available once the primary publications are published.
• Access Criteria: Only for collaborative research purposes with a separate agreement with the data owner, the accessibility of data and documents can be decided together.

Locations

FI (2)