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

University of Turku

Status: Active, not recruiting

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

Treatments: Other: Dietary intervention; Other: Postprandial meal test

Study type: Interventional

Funder types: Other

Identifiers

NCT05526092

OGB

Details and patient eligibility

About

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.

Full description

Aims in this 6-week randomised, single-blinded clinical trial, including a postprandial study, with metabolically challenged volunteers on oat-rich low-gluten diet, are to:

1. Compare effect of oat and rice rich diets to blood lipid and glucose status, perceived gut and general well-being and dietary intake.
2. Investigate changes in fecal microbiome, SCFAs, plasma antioxidant status and inflammation markers resulting from consumption of oat or rice rich low-gluten diets.
3. Examine the impact of the oat or rice-rich low-gluten diet on the change in metabolite profiles in blood by non-targeted metabolomics approach.
4. Find out the long-term effects of oat and rice consumption on recovery and vitality by modulating the gut-brain axis and measured with neuropsychological testing and using tryptophan metabolites as biomarkers.
5. Discover how the long-term consumption of oats and rice and their possible alterations in fecal microbiome affect subsequent postprandial glycaemia and response of microbiota to the meal (as seen in plasma SCFAs).

Enrollment: 72 patients

Sex: All

Ages: 30 to 68 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Commits to follow the instructed low-gluten diet for 6 weeks
• 30 - 68 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).

Exclusion criteria

• 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)

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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72 participants in 4 patient groups

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

Experimental group

Description:

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.

Treatment:

Other: Postprandial meal test

Other: Dietary intervention

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

Active Comparator group

Description:

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.

Treatment:

Other: Postprandial meal test

Other: Dietary intervention

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

Experimental group

Description:

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.

Treatment:

Other: Postprandial meal test

Other: Dietary intervention

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

Active Comparator group

Description:

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.

Treatment:

Other: Postprandial meal test

Other: Dietary intervention