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

Not Applicable
Active, not recruiting
Conditions
High Blood Pressure
Overweight and Obesity
High Cholesterol/Hyperlipidemia
Interventions
Other: Dietary intervention
Registration Number
NCT05526092
Lead Sponsor
University of Turku
Brief Summary

The overall objective of this research entity is to reveal the holistic 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 plasma lipids, plasma antioxidant status, fecal microbiota and fecal bile acids. Additionally the effect of the 6-week diet on posptprandial glycemia and postprandial satiety and vitality are investigated.

Detailed Description

Aims in this 6-week randomised, single-blinded clinical trial, including a postprandial study at the 6 week time point, 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 well-being and diet quality.

2. Investigate changes in microbiota, 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 and rice rich gluten free diet on the change in metabolite profiles in blood.

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 markers.

5. Discover how the long-term consumption of oats and rice and their possible alterations in gut microbiota affect subsequent postprandial glycaemia and response of microbiota to the meal (as seen in plasma SCFAs).

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
72
Inclusion Criteria
  • Commits to follow low-gluten diet for 6 weeks
  • 30 - 68 years of age
  • BMI > 25 kg/m^2
  • High cholesterol AND/OR Hypertension
Exclusion Criteria
  • Regular medication that can affect the gut
  • Pregnancy or lactation
  • Recent course of antibiotics (less than 3 months prior to the study)

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Oat-rich and low-gluten dietDietary interventionParticipants will consume oats and oat products and follow low-gluten diet for 6 weeks.
Rice-rich and low-gluten dietDietary interventionParticipants will consume rice and rice products and follow low-gluten diet for 6 weeks.
Primary Outcome Measures
NameTimeMethod
Changes in inflammation markersWeek 0 and 6

The inflammation markers in plasma are measured as a baseline before the study and after 6 week diet intervention. The markers will be analysed with cDNA multiplex immunoassay and qPCR giving semi-quantitative results on a log2 scale (Olink inflammation panel, Olink Proteomics, Uppsala, Sweden). The panel contains at least 92 different proteins that are related to inflammation.

Changes in neuropsychological performance: cognitive loadWeek 0 and 6

Established and well-validated computerised neuropsychological tests to measure cognitive load will be conducted both at the beginning and at the end of the intervention in connection with postprandial test. Inquisit software (Millisecond Software, Seattle, Washington, USA; https://www.millisecond.com/download/library/) is used for the cognitive load (Serial Sevens Task) test.

Changes in neuropsychological performance: reaction time and attentionWeek 0 and 6

Established and well-validated computerised neuropsychological tests to measure cognitive load will be conducted both at the beginning and at the end of the intervention in connection with postprandial test. Inquisit software (Millisecond Software, Seattle, Washington, USA; https://www.millisecond.com/download/library/) is used for the reaction time and attention (Color Word Stroop test) test.

Changes in neuropsychological performance: response controlWeek 0 and 6

Established and well-validated computerised neuropsychological tests to measure cognitive load will be conducted both at the beginning and at the end of the intervention in connection with postprandial test. Inquisit software (Millisecond Software, Seattle, Washington, USA; https://www.millisecond.com/download/library/) is used for the response control (Cued Go/No-Go Task) test.

Changes from baseline in plasma short-chain fatty acidsWeek 0 and 6

Samples are taken 90 and 180 min after consuming the study meal, and at the fasting state, before and after the 6-week diet intervention to see the change between fasting state and postprandial states.

Changes from baseline in plasma antioxidant capasityWeek 0 and 6

Plasma samples are taken 180 min after consuming the study meal, and at the fasting state, before and after the 6-week diet intervention to see the change between fasting state and postprandial states. The antioxidant status of plasma will be analysed with commercial kits for 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and Oxygen Radical Absorbance Capacity (ORAC) (Merck KGaA, Darmstadt, Germany) to measure antioxidant capacity of plasma.

Changes in blood lipidWeek 0 and 6

Postprandial plasma samples are taken at the fasting state and 15, 30, 45, 60, 90, 120 and 180 min after consuming the study meal before, and after the 6-week diet intervention to see blood lipid development curve in postprandial state.

Changes in glucose statusWeek 0 and 6

Postprandial plasma samples are taken at the fasting state and 15, 30, 45, 60, 90, 120 and 180 min after consuming the study meal before, and after the 6-week diet intervention to see blood glucose development curve in postprandial state.

Secondary Outcome Measures
NameTimeMethod
Changes in gut microbiotaWeek 0 and 6

Changes in gut microbiota during the dietary intervention as seen in sequencing the fecal samples from the study participants before and after the 6-week dietary intervention.

Changes in gastrointestinal symptomsWeeks 0 and 6

Gastrointestinal symptoms (self-reported) during a postprandial study as measured by a questionnaire. The questionnaire is divided into seven types of gastrointestinal discomfort, and also includes a possibility to describe a gastrointestinal discomfort outside these seven given alternatives. The severity of the symptoms is self-reported on a three-step scale (0 as mild or no symptoms, 1 as moderate symptoms, 2 as strong symptoms).

Changes in excreted bile acidsWeek 0 and 6

Changes in excreted bile acids during the dietary intervention analyses from the fecal samples of the study participants before and after the 6-week dietary intervention.

Trial Locations

Locations (2)

Food Chemistry and Food Development, Department of Life Technologies, University of Turku

🇫🇮

Turku, Finland

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

🇫🇮

Kuopio, Finland

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