Barley and Rice Mixture Effects on Blood Glucose

Study Overview
=================
Brief Summary
-----------------
The purpose of this research was to investigate 5 different formulations of whole grain barley and refined white rice against a control of white bread on post-prandial glycemic response, as well as self-reported hunger/satiety in a randomized cross-over trial.

Detailed Description
-----------------
Beta-glucan-rich barley has been shown to improve glycemic response, reduce hunger and increase satiety. Nutrient-dense grain mixtures that include a new cultivar of barley (Sustagrain, Ardent Mills, LLC) with exceptionally high dietary fiber content may help individuals meet their dietary fiber needs while minimizing the rapid increase in blood glucose following the consumption of a refined grain product. The primary objective of this study was to compare the effects of five different test meals containing varying amounts of whole-grain barley and refined white rice to white bread on post-prandial blood glucose concentrations. A secondary aim was to evaluate changes in self-reported hunger and satiety following the consumption of each treatment. This study was a single-site, blinded, randomized crossover trial among 24 healthy adults. Each participant consumed the following treatments: 100% Sustagrain barley flakes, 100% Sustagrain steel cut barley , an 80/20 rice-steel cut Sustagrain barley mix, a 50/50 rice-steel cut Sustagrain barley mix, 100% rice, and white bread.

Official Title
-----------------
β-glucan Rich Barley and Rice Mixes and Post-prandial Glycemia - a Dose Response Study

Conditions
-----------------
Blood Glucose, Dietary Fiber, Hunger

Intervention / Treatment
-----------------
* Other: 100% steel cut barley
* Other: 100% barley flakes
* Other: 50/50 rice-barley mix
* Other: 80/20 rice-barley mix
* Other: 100% rice
* Other: white bread


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Healthy, English speaking adults; BMI between 18 and 30 kg/m2 Exclusion Criteria: History of GI malabsorption diseases, food allergy or intolerance to gluten; Prediabetes, and/or diabetes, and/or treatment with diabetic medications for any reason; Hypertension, hypothyroidism and other chronic disease that affects nutrient metabolism; Any women pregnant or lactating, or expecting to become pregnant during the study; Individuals with a history of bleeding disorders

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Otherwise healthy male and female adults
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: bread-50/50-steelcut-80/20-flake-rice<br>25 g of available carbohydrate was delivered to participants via (1) white bread, followed by (2) 50/50 rice-barley mix, followed by (3) 100% steel cut barley, followed by (4) 80/20 rice-barley mix, followed by (5) 100% barley flakes, followed by (6) 100% rice | Other: 100% steel cut barley<br>* 25 g of available carbohydrate was delivered to participants via steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% barley flakes<br>* 25 g of available carbohydrate was delivered to participants via Sustagrain barley flakes (Ardent Mills, LLC).<br>Other: 50/50 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 50/50 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 80/20 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 80/20 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% rice<br>* 25 g of available carbohydrate was delivered to participants via Goya medium grain white rice<br>Other: white bread<br>* 25 g of available carbohydrate was delivered to participants via Sara Lee Classic White Bread (Bimbo Bakeries USA, Inc.)<br>|
| Experimental: 50/50-steelcut-80/20-flake-rice-bread<br>25 g of available carbohydrate was delivered to participants via (1) 50/50 rice-barley mix, followed by (2) 100% steel cut barley, followed by (3) 80/20 rice-barley mix, followed by (4) 100% barley flakes, followed by (5) 100% rice, followed by (6) white bread | Other: 100% steel cut barley<br>* 25 g of available carbohydrate was delivered to participants via steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% barley flakes<br>* 25 g of available carbohydrate was delivered to participants via Sustagrain barley flakes (Ardent Mills, LLC).<br>Other: 50/50 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 50/50 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 80/20 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 80/20 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% rice<br>* 25 g of available carbohydrate was delivered to participants via Goya medium grain white rice<br>Other: white bread<br>* 25 g of available carbohydrate was delivered to participants via Sara Lee Classic White Bread (Bimbo Bakeries USA, Inc.)<br>|
| Experimental: steelcut-80/20-flake-rice-bread-50/50<br>25 g of available carbohydrate was delivered to participants via (1) 100% steel cut barley, followed by (2) 80/20 rice-barley mix, followed by (3) 100% barley flakes, followed by (4) 100% rice, followed by (5) white bread, followed by (6) 50/50 rice-barley mix | Other: 100% steel cut barley<br>* 25 g of available carbohydrate was delivered to participants via steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% barley flakes<br>* 25 g of available carbohydrate was delivered to participants via Sustagrain barley flakes (Ardent Mills, LLC).<br>Other: 50/50 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 50/50 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 80/20 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 80/20 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% rice<br>* 25 g of available carbohydrate was delivered to participants via Goya medium grain white rice<br>Other: white bread<br>* 25 g of available carbohydrate was delivered to participants via Sara Lee Classic White Bread (Bimbo Bakeries USA, Inc.)<br>|
| Experimental: 80/20-flake-rice-bread-50/50-steelcut<br>25 g of available carbohydrate was delivered to participants via (1) 80/20 rice-barley mix, followed by (2) 100% barley flakes, followed by (3) 100% rice, followed by (4) white bread, followed by (5) 50/50 rice-barley mix, followed by (6) 100% steel cut barley | Other: 100% steel cut barley<br>* 25 g of available carbohydrate was delivered to participants via steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% barley flakes<br>* 25 g of available carbohydrate was delivered to participants via Sustagrain barley flakes (Ardent Mills, LLC).<br>Other: 50/50 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 50/50 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 80/20 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 80/20 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% rice<br>* 25 g of available carbohydrate was delivered to participants via Goya medium grain white rice<br>Other: white bread<br>* 25 g of available carbohydrate was delivered to participants via Sara Lee Classic White Bread (Bimbo Bakeries USA, Inc.)<br>|
| Experimental: flake-rice-bread-50/50-steelcut-80/20<br>25 g of available carbohydrate was delivered to participants via (1) 100% barley flakes, followed by (2) 100% rice, followed by (3) white bread, followed by (4) 50/50 rice-barley mix, followed by (5) 100% steel cut barley, followed by (6) 80/20 rice-barley mix | Other: 100% steel cut barley<br>* 25 g of available carbohydrate was delivered to participants via steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% barley flakes<br>* 25 g of available carbohydrate was delivered to participants via Sustagrain barley flakes (Ardent Mills, LLC).<br>Other: 50/50 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 50/50 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 80/20 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 80/20 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% rice<br>* 25 g of available carbohydrate was delivered to participants via Goya medium grain white rice<br>Other: white bread<br>* 25 g of available carbohydrate was delivered to participants via Sara Lee Classic White Bread (Bimbo Bakeries USA, Inc.)<br>|
| Experimental: rice-bread-50/50-steelcut-80/20-flake<br>25 g of available carbohydrate was delivered to participants via (1) 100% rice, followed by (2) white bread, followed by (3) 50/50 rice-barley mix, followed by (4) 100% steel cut barley, followed by (5) 80/20 rice-barley mix, followed by (6) 100% barley flakes | Other: 100% steel cut barley<br>* 25 g of available carbohydrate was delivered to participants via steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% barley flakes<br>* 25 g of available carbohydrate was delivered to participants via Sustagrain barley flakes (Ardent Mills, LLC).<br>Other: 50/50 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 50/50 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 80/20 rice-barley mix<br>* 25 g of available carbohydrate was delivered to participants via a 80/20 mixture (by weight) of Goya medium grain white rice and steel cut Sustagrain barley (Ardent Mills, LLC).<br>Other: 100% rice<br>* 25 g of available carbohydrate was delivered to participants via Goya medium grain white rice<br>Other: white bread<br>* 25 g of available carbohydrate was delivered to participants via Sara Lee Classic White Bread (Bimbo Bakeries USA, Inc.)<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-prandial glycemia | Incremental area under the curve(iAUC) for plasma glucose concentrations were measured at 0, 15, 30, 45, 60, 90 and 120 min using the trapezoidal method to evaluate the glycemic response to each grain treatment. | 0 min, 15 min, 30 min, 45min , 60 min, 90 min, 120 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Self-reported hunger | Visual analog scales were used to evaluate self-reported feelings of hunger using the question How hungry do you feel? The scale consisted of a 100-millimeter line with anchors I am not hungry at all and I have never been more hungry at 0 and 100 millimeters, respectively. Lower numbers represent low feelings of hunger while larger values are characteristic of greater hunger. Hunger was assessed at 0, 15, 30, 60, 90 and 120 minutes to evaluate changes across time for each grain treatment. | 0 min, 15 min, 30 min, 60 min, 90 min, 120 min | 
| Self-reported satiety | Visual analog scales were used to evaluate self-reported feelings of satiety using the question How satisfied do you feel? The scale consisted of a 100-millimeter line with anchors I am completely empty and I cannot eat another bite at 0 and 100 millimeters, respectively. Lower numbers represent low feelings of satiety while larger values are characteristic of greater satiety. Satiety was assessed at 0, 15, 30, 60, 90 and 120 minutes to evaluate changes across time for each grain treatment. | 0 min, 15 min, 30 min, 60 min, 90 min, 120 min | 
| Self-reported fullness | Visual analog scales were used to evaluate self-reported feelings of fullness using the question How full do you feel? The scale consisted of a 100-millimeter line with anchors Not at all full and Totally full at 0 and 100 millimeters, respectively. Lower numbers represent low feelings of fullness while larger values are characteristic of greater fullness. Fullness was assessed at 0, 15, 30, 60, 90 and 120 minutes to evaluate changes across time for each grain treatment. | 0 min, 15 min, 30 min, 60 min, 90 min, 120 min | 
| Self-reported prospective food consumption | Visual analog scales were used to evaluate self-reported feelings toward prospective food consumption using the question How much do you think you can eat? The scale consisted of a 100-millimeter line with anchors Nothing at all and A lot at 0 and 100 millimeters, respectively. Lower numbers represent low ability to eat while larger values are characteristic of greater ability to eat. Prospective food consumption was assessed at 0, 15, 30, 60, 90 and 120 minutes to evaluate changes across time for each grain treatment. | 0 min, 15 min, 30 min, 60 min, 90 min, 120 min | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
glucose, dietary fiber, glycemia, whole grain