High-amylose Barley (HIAMBA) in the Regulation and Prevention of Type 2 Diabetes

High-amylose Barley (HIAMBA) in the Regulation and Prevention of Type 2 Diabetes: a Randomized, Cross-over, Acute Dietary Intervention Study.

In a series of double-blinded randomized cross-over acute studies, the investigators want to study the effects of naturally produced high-amylose barley (HIAMBA®) on the postprandial glucose-metabolism in subjects with and without type 2 diabetes (T2D).

The prevalence of T2D is increasing worldwide, primarily due to obesity, lack of physical activity and unhealthy diet. Therefore, it is of great important to evolve dietary products that counteracts this development. Barley has shown some beneficial effects on postprandial blood glucose compared with wheat. A lowering of the postprandial glucose level reduces the risk of developing T2D and helps in the regulation of a pre-existing diabetes. However, barley is traditionally not used in bread-making in Denmark. The elevation of postprandial glucose also depends on how fast the dietary products are degraded in the gastrointestinal tract. The starch in barley consist of both fastly degraded amylopectin and slowly degraded amylose. Slow degradation is expected to lower postprandial glucose. By natural breeding techniques it has been possible for the investigators collaborative partners at the Universities of Aarhus and Copenhagen and PlantCarb ApS to make an natural organic high-amylose barley (HIAMBA®). In a series of acute studies the investigators want to study the effects on the glycemic response to bread made with different compositions of wheat and HIAMBA® in subjects with T2D. The investigators expect that HIAMBA® positively affect the postprandial glucose-metabolism more than wheat and hereby acutely improves the glycemic regulation for both subjects with and without T2D.

Adults with T2D. Hemoglobin A1C between 48-78 mmol/l. No use of insulin or once-weekly glucagon-like peptide-1 (GLP-1) or acarbose. No severe cardiovascular, kidney, liver, psychiatric or endocrine disease. No abuse of alcohol- or narcotics. No pregnancy or lactation.

Adults without T2D. No severe cardiovascular, kidney, liver, psychiatric or endocrine disease. No abuse of alcohol- or narcotics. No pregnancy or lactation.

Intake of 250 ml of tap water and 100 g of bread baked with 100% wheat flour (regular commercial available wheat flour). Consumed over maximum 10 minutes at time 0 min after overnight fasting. At one of four visits.

Intake of 250 ml of tap water and 100 g of bread baked with 50% HIAMBA® flour and 50% wheat flour. Consumed over maximum 10 minutes at time 0 min after overnight fasting. At one of four visits. HIAMBA® are naturally bred in corporation with PlantCarb ApS and researchers at Aarhus and Copenhagen Universities. The wheat flour is standard commercial available flou

Intake of 250 ml of tap water and 100 g of bread baked with 75% HIAMBA® flour and 25% wheat flour. Consumed over maximum 10 minutes at time 0 min after overnight fasting. At one of four visits. HIAMBA® are naturally bred in corporation with PlantCarb ApS and researchers at Aarhus and Copenhagen Universities. The wheat flour is standard commercial available flour.

Intake of 250 ml of tap water and 100 g of bread baked with 50% nude barley flour and 50% wheat flour. Consumed over maximum 10 minutes at time 0 min after overnight fasting. At one of four visits. Ancient nude barley naturally bred in corporation with PlantCarb ApS and researchers at Aarhus and Copenhagen Universities. The wheat flour is standard commercial available flour.

Time Frame: Change from -10 minutes to 240 minutes after bread intake (measured at time -10,0,10,20,30,45,60,90,120,150,180,210,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,10,20,30,45,60,90,120,150,180,210,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,10,20,30,45,60,90,120,150,180,210,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,30,60,120,180,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,30,60,120,180,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,30,60,120,180,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,30,60,120,180,240,300,360 minutes)

Change from -10 minutes to 240 minutes after bread (measured at time -10,0,30,60,120,180,240,300,360 minutes)

Area under the curve for SCFA (acid, proprionic acid, butyric acid, valeric acid, iso-valeric acid, iso-butyric acid and succinate). Targeted liquid-chromatography mass spectrometry (LC-MS) is used to quantify plasma SCFA.

Change from -10 minutes to 240 minutes after bread (measured at time 0,60,120,180,240,300,360 minutes)

Area under the curve for blood metabolomics (low-molecular-weight compounds/metabolites present in human biofluids). Using non-targeted liquid-chromatography mass spectrometry (LC-MS) approch.

Change from -10 minutes to 240 minutes after bread (measured at time 0,60,120,180,240,300,360 minutes)

VAS-score of a number of standardized questions regarding, hunger, satiety, the test meal experience etc. Each answer is ranged on a 100 mm line expressing the most positive and negative rating possible at each end.

Inclusion Criteria for T2D group: T2D defined by standard Danish guidelines. HbA1c between 48-78 mmol/l. Treatment with drugs for hypertension and high cholesterol is allowed if the treatment dose is stable and does not demand changes during the study period. Participants are encouraged to maintain their present psychical activity level and their smoking and alcohol habits. Exclusion Criteria: Type 1 diabetes Insulin demanding T2D Use of weekly administrated GLP-1 antagonist (e.g. ozempic, trulicity or byetta) Use of acarbose Significant cardiovascular, kidney, liver or endocrine comorbidity Significant psychiatric history Treatment with steroids Alcohol or drug abuse Pregnancy or breastfeeding Legally incompetent