Effects of Berries on Post-meal Blood Sugar

Study Overview
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Brief Summary
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The purpose of this study is to investigate whether berries are effective in lowering blood glucose and insulin responses to meals containing starch or sucrose.

Detailed Description
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Berries are rich sources of various polyphenols which may be beneficial in the regulation of blood glucose. In vitro and animal studies have shown that polyphenols and polyphenol-rich extracts of foods, including berries, may inhibit digestion and absorption of carbohydrates and thereby suppress postprandial glycemia. However, current evidence on the effects of berries on postprandial glycemic responses in humans is limited. The purpose of this study is to investigate the effects of berries on postprandial glycemic responses (blood glucose and insulin) to starch or sucrose in healthy subjects. It consists of five substudies each of which includes 2-4 meals with different berry species typically consumed in Finland and a reference meal without berries. The following combinations of carbohydrates and berries are studied: Studies 1-2: white wheat bread (starch) is consumed with several berry species Study 3: white wheat bread or rye bread is consumed with a mixture of berries Study 4: sugar (sucrose) is consumed with berries and berry nectars Study 5: a sugar-sweetened bakery product (starch + sucrose) is consumed with berries and berry nectar.

Official Title
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Effects of Berries on Postprandial Glycemic Responses to Sucrose and Starch

Conditions
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Blood Glucose, Postprandial, Blood Insulin, Postprandial, Hyperglycemia

Intervention / Treatment
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* Other: Berries
* Other: No berries


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI 20-28 kg/m2 normal fasting plasma glucose Exclusion Criteria: Smoking Diabetes or other chronic disease Antibiotic medication within the past 3 months Blood donation within the past month

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 69 Years


Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Berry meal<br>Carbohydrate meals with berries | Other: Berries<br>* Meals containing starch (bread) or sucrose are consumed with berries (150 g) or berry nectars (300 mL).<br>|
| Active Comparator: Reference meal<br>Carbohydrate meals without berries | Other: No berries<br>* Meals containing starch (bread) or sucrose are consumed without berries.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma glucose |  | 0, 15, 30, 45, 60, 90, 120 minutes post-meal | 
| Plasma insulin |  | 0, 15, 30, 45, 60, 90, 120 minutes post-meal | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma free fatty acids |  | 0, 15, 30, 45, 60, 90, 120 minutes post-meal | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Berries, Starch, Sucrose, Glucose, Insulin, Postprandial