Effects of Beta-glucan From Barley and Oats on Glucose and Lipid Metabolism, and Satiety (gLUCAn)

Intervention Study - Physiological Short-term and Long-term Effects of Regularly Consumption of Beta-glucan From Barley and Oats on the Glucose and Lipid Metabolism and Satiety

The interventional study will evaluate the effects of a regularly consumption of barley and oat flakes in crude and roasted form on the glucose and lipid metabolism as well as the postprandial saturation. Moreover, the study will evaluate the effect of a regularly consumption of barley and oat flakes on the glucose and lipid metabolism over a period of three weeks.

All participants will run through each intervention (cross-over design). Inbetween these intervention periods there will be wash-out phases. In total there will be four interventions: crude oat flakes, roasted oat flakes, crude barley flakes and roasted barley flakes. The comparison will be made against white toastbread. The study participants will visit the study centrum before and after each intervention over an entire period of 27 weeks.

Study Overview

• Status: Completed
• Conditions: Glucose Metabolism; Lipid Metabolism; Satiety
• Intervention / Treatment: Dietary supplement: Intervention 1; Dietary supplement: Intervention 2; Dietary supplement: Intervention 3; Dietary supplement: Intervention 4; Dietary supplement: Control

Detailed Description

The interventional study will evaluate the effects of a regularly consumption of barley and oat flakes in crude and roasted form on the glucose and lipid metabolism as well as the postprandial saturation. Moreover, the study will evaluate the effect of a regularly consumption of barley and oat flakes on the glucose and lipid metabolism over a period of three weeks.

By applying the cross-over design, all participants will run through each intervention. In total there will be four interventions: crude oat flakes, roasted oat flakes, crude barley flakes and roasted barley flakes. Each intervention period will last three weeks and will be separated by wash-out phases which also will last three weeks. The comparison will be made against white toastbread, which will be the fifth intervention. The entire duration of the study will be 27 weeks (5x 3 weeks intervention + 4x 3 weeks wash-out phases inbetween).

The participants will visit the study centrum before and after each intervention for examinations and for taking blood samples. During the examination the participants will receive a test-meal to evaluate postprandial blood glucose and insulin levels. Moreover, the kinetic of hormones that influence the satiety will be evaluated. In addition to the examination of blood samples, the microbiota of feces will be examined.

During the intervention periods the participants will receive recipes for breakfast for 21 days. In these recipes 80 gram oat or barley flakes or four slices of white toastbread will be included.

The study will provide data about the association between different processed cereals and measurable markers reflecting glucose and lipid metabolism as well as their influence on hormones of satiety and microbiota.

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Thuringia
    • Jena, Thuringia, Germany, 07743
      • Friedrich-Schiller-University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• LDL-cholesterol ≥ 120 mg/dl (≥ 3 mmol/l)
• Typical western diet

Exclusion Criteria:

• intake of lipid-lowering medications
• gastrointestinal diseases
• diabetes mellitus type I and II
• familial hypercholesterolemia
• intake of additional dietary supplements (especially ß-glucan capsules, high-fibre compounds)
• pregnancy, lactation
• appreciable food allergies/intolerances
• patient´s request or if patient compliance with the study protocol is doubtful

Study Plan

How is the study designed?

Design Details

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

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Intervention 1; Intervention 1: Crude oat flakes (dietary supplement) 80 g of crude oat flakes contain 4 g ß-glucan. According to the current Health Claim, 4 g ß glucan are necessary to achieve a reduction of the postprandial glycemic answer and a reduction of the cholesterol concentration in hypercholesterolinaemic patients. The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of crude oat flakes.	Dietary supplement: Intervention 1; The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of crude oat flakes per day.; Other Names: Crude oat flakes
Active Comparator: Intervention 2; Roasted oat flakes (dietary supplement) 80 g of roasted oat flakes contain 4 g ß-glucan. According to the current Health Claim, 4 g ß-glucan are necessary to achieve a reduction of the postprandial glycemic answer and a reduction of the cholesterol concentration in hypercholesterolinaemic patients. These oat flakes were roasted at 150°C for 20 minutes. The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of roasted oat flakes.	Dietary supplement: Intervention 2; The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of roasted oat flakes per day.; Other Names: Roasted oat flakes
Active Comparator: Intervention 3; Crude barley flakes (dietary supplement) 80 g of crude oat flakes contain 4 g ß-glucan. According to the current Health Claim, 4 g ß-glucan are necessary to achieve a reduction of the postprandial glycemic answer and a reduction of the cholesterol concentration in hypercholesterolinaemic patients. The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of crude barley flakes	Dietary supplement: Intervention 3; The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of crude barley flakes per day.; Other Names: Crude barley flakes
Active Comparator: Intervention 4; Roasted barley flakes (dietary supplement) 80 g of roasted oat flakes contain 4 g ß-glucan. According to the current Health Claim, 4 g ß-glucan are necessary to achieve a reduction of the postprandial glycemic answer and a reduction of the cholesterol concentration in hypercholesterolinaemic patients. The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of roasted barley flakes.	Dietary supplement: Intervention 4; The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of roasted barley flakes per day.; Other Names: Roasted barley flakes
Placebo Comparator: control; White toastbread (control) (dietary supplement) White toastbread was chosen because of its low fibre content. To achieve the same energy value (kcal) as 80 g cereal flakes the participants have to consume four slices of white toastbread. The study participants receive recipes for breakfast for 21 days. The recipes imply four slices of white toastbread.	Dietary supplement: Control; White toastbread (control) (dietary supplement) White toastbread was chosen because of its low fibre content. To achieve the same energy value (kcal) as 80 g cereal flakes the participants have to consume four slices of white toastbread. The study participants receive recipes for breakfast for 21 days. The recipes imply four slices of white toastbread.; Other Names: White toast bread

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
LDL cholesterol	LDL cholesterol [mmol/L]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No] [mmol/L]

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
total cholesterol	total cholesterol [mmol/L]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No] total cholesterol, LDL cholesterol, HDL cholesterol, triacylglycerides (TAG) [mmol/L]
HDL cholesterol	HDL cholesterol [mmol/L]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No] total cholesterol, LDL cholesterol, HDL cholesterol, triacylglycerides (TAG) [mmol/L]
triacylglycerides	triacylglycerides [mmol/L]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No] total cholesterol, LDL cholesterol, HDL cholesterol, triacylglycerides (TAG) [mmol/L]
HOMA-index	HOMA-index	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
fasting blood glucose	fasting blood glucose [mg/dl]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
kinetic of glycemic answer	blood glucose (mg/dl; timepoints: 0, 30, 60, 120 and 180 min) after a test meal)	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
kinetic of satiety hormones	Ghrelin, GLP1, peptide YY (timepoints: 0, 30, 60, 120 and 180 min) after a test meal)	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
short chain fatty acids in fecal water	short chain fatty acids (SCFA; %) , pH value, composition of microbiome	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
composition of microbiome	composition of microbiome [%]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
blood pressure	systolic and diastolic blood pressure [mmHg]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
height	Height [m]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
weight	Weight [kg]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
body-mass index	body-mass index [kg/m2]	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]
bioelectrical impedance analysis	bioelectrical impedance analysis (%)	[Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No]

Collaborators and Investigators

• Sponsor: University of Jena

Publications and helpful links

Helpful Links

• Study results

Study record dates

Study Major Dates

• Study Start (Actual): May 2, 2018
• Primary Completion (Actual): May 31, 2018
• Study Completion (Actual): July 31, 2019

Study Registration Dates

• First Submitted: August 21, 2018
• First Submitted That Met QC Criteria: August 23, 2018
• First Posted (Actual): August 27, 2018

Study Record Updates

• Last Update Posted (Estimate): February 22, 2023
• Last Update Submitted That Met QC Criteria: February 18, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: insulin; microbiota; dietary fibres; fasting glucose; ß-glucan; low-density-lipoprotein-cholesterol
• Other Study ID Numbers: H7_18

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No