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

University of Jena32 enrolled

Overview

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

Interventions

Intervention 1DIETARY_SUPPLEMENT

The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of crude oat flakes per day.

Intervention 2DIETARY_SUPPLEMENT

The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of roasted oat flakes per day.

Intervention 3DIETARY_SUPPLEMENT

The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of crude barley flakes per day.

Intervention 4DIETARY_SUPPLEMENT

The study participants receive recipes for breakfast for 21 days. The recipes imply 80 g of roasted barley flakes per day.

ControlDIETARY_SUPPLEMENT

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.

Eligibility

Sex: ALLMin age: 25 YearsMax age: 65 YearsHealthy volunteers:

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

LDL cholesterol

LDL cholesterol \[mmol/L\]

Time frame: [Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No] [mmol/L]

Secondary Outcomes

total cholesterol

total cholesterol \[mmol/L\]

Time frame: [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: [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: [Time Frame: change from baseline to 3 weeks intervention] [Safety Issue: No] total cholesterol, LDL cholesterol, HDL cholesterol, triacylglycerides (TAG) [mmol/L]

HOMA-index