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Effect of 6-week Strawberry Supplementation on Insulin Action (STR2)

Primary Purpose

Insulin Resistance, Nutritional Disease, Metabolic Disease

Status
Completed
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Strawberry
Placebo1
Placebo2
Sponsored by
Clinical Nutrition Research Center, Illinois Institute of Technology
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Insulin Resistance focused on measuring Insulin Resistant, Dietary Supplements, Nutrition, Antioxidant, Inflammation

Eligibility Criteria

18 Years - 65 Years (Adult, Older Adult)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

  • Must meet ONE or MORE of the criteria (1)-(5) associated with insulin resistance along with all other criteria listed (6)-(9):

    1. Blood glucose concentration between140-199 mg/dL at 2hr from OGTT.
    2. Elevated fasting glucose (110 mg/dL≤ Fasting blood glucose <126 mg/dL)
    3. Elevated fasting insulin (>75th percentile cutoff of 13.13 μU/mL)
    4. Insulin resistance defined by the homeostasis model assessment method of insulin resistance (HOMA-IR) (glucose [in millimoles per liter] × insulin [in microunits per milliliter]/22.5) values of at least 2.5.
    5. Waist circumference ≥ 110 cm because many epidemiology studies have been shown that waist circumferences may be related to insulin resistance.
    6. Nonsmokers
    7. Not taking any medications that would interfere with outcomes of the study, i.e. lipid lowering medications, anti-inflammatory drugs, or dietary supplements
    8. 18 years of age and older
    9. No clinical evidence of cardiovascular, metabolic, respiratory, renal, gastrointestinal or hepatic disease

Exclusion Criteria:

  • Pregnant and/or lactating.

    • Allergy or intolerance to strawberries and dairy products.
    • Current regular consumption of strawberries is > 2 servings per day.
    • Fasting blood glucose ≥ 126 mg/dL. Subjects identified with elevated fasting blood glucose levels will be advised to contact their primary care physician for appropriate follow-up care.
    • Taking over the counter antioxidant supplements or other supplements that may interfere with the study procedures or endpoints.
    • Subjects with unusual dietary habits (e.g. pica).
    • Actively losing weight or trying to lose weight (unstable body weight fluctuations of > 5 kg in a 60 day period).
    • Excessive exercisers or trained athletes.
    • Subjects with documented atherosclerotic disease, inflammatory disease, diabetes mellitus, or other systemic diseases.
    • Addicted to drugs and/or alcohol.
    • Medically documented psychiatric or neurological disturbances.
    • Smoker (past smoker may be allowed if cessation is > 2 years).

Sites / Locations

  • Clinical Nutrition Research Center

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm Type

Placebo Comparator

Active Comparator

Placebo Comparator

Arm Label

Placebo1

Strawberry

Placebo2

Arm Description

Placebo Beverage 1 without fiber

Strawberry Beverage 20g/BID

Placebo Beverage 2 with Fiber

Outcomes

Primary Outcome Measures

The chronic beneficial effect of polyphenolics from strawberry on impaired insulin signaling in insulin-resistant men and women
Subjects will be randomized to receive either one of beverages, Pbo1, Pbo2 or Str Beverage and consume randomly assigned beverage twice per day with their breakfast and dinner meals for 6 weeks. On visits at Wk0, Wk6, and Wk10, blood will be collected at 0h, and 1h, 2h, 3h and 4h time points following the 75 g glucose load (oral glucose tolerance test) and Flow Mediated Dilation (FMD) procedure will be performed as well.

Secondary Outcome Measures

The chronic beneficial effect of polyphenolics from strawberry on oxidative- and inflammatory-markers in insulin-resistant men and women
Samples of venous blood will be collected for measurement of oxidative and inflammatory markers (hs-CRP levels, LDL oxidation, Interleukin (IL)-6 and other inflammatory molecules, Total antioxidant levels of the blood)

Full Information

First Posted
October 19, 2011
Last Updated
February 7, 2023
Sponsor
Clinical Nutrition Research Center, Illinois Institute of Technology
Collaborators
California Strawberry Commission
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1. Study Identification

Unique Protocol Identification Number
NCT01457612
Brief Title
Effect of 6-week Strawberry Supplementation on Insulin Action (STR2)
Official Title
Effect of 6 Weeks Strawberry Supplementation on Insulin Action and Associated Risk Factors in Insulin Resistant (IR) Subjects (STR2)
Study Type
Interventional

2. Study Status

Record Verification Date
February 2023
Overall Recruitment Status
Completed
Study Start Date
October 1, 2011 (Actual)
Primary Completion Date
December 1, 2012 (Actual)
Study Completion Date
March 1, 2013 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Clinical Nutrition Research Center, Illinois Institute of Technology
Collaborators
California Strawberry Commission

4. Oversight

Data Monitoring Committee
No

5. Study Description

Brief Summary
The primary study objective is to investigate the potential chronic beneficial effect of polyphenolics derived from strawberry on impaired insulin signaling in insulin resistant individuals through their ability to modulate oxidative- and inflammatory-markers that lead to devastating disease, including, but not limited to, diabetes and cardiovascular disease.
Detailed Description
This study is a single-center, randomized and single blinded, placebo-controlled, 6-week, parallel design study with follow-up to evaluate strawberry-associated chronic improvements in insulin action resulting in reduced whole body insulin resistance and improved glucose tolerance. This study will take approximately 11~12 weeks. Subjects will follow an extremely limited polyphenolic diet throughout the duration of their participation in the study. The limited diet will begin 7 days before the first study visit and end before the last study visit. Following the polyphenol-free 7-day run in period, at Week 0, subjects will be scheduled to return to the Center for sequence randomization, an Oral Glucose Tolerance Test (OGTT) as well as a Flow Mediated Dilation (FMD) procedure to measure endothelial function. Subjects will incorporate either one of tow Placebo Beverages (PBO1, n=15; PBO2, n=15) or Strawberry Beverage (STR, n=15, an optimal strawberry test dose of 40 g/d) into their diet daily for a period of 6 weeks. Subjects will consume randomly assigned beverage twice per day with their breakfast and dinner meals. All subjects will be asked to come to the Center once a week where they will receive a week's supply of beverages. Additionally, fasting clinical and laboratory variables, anthropometrics, and vital sign measurements will be assessed at each bi-weekly visit at Week 3 and Week 5. Participants will undergo the same procedures at the end of Week 6: fasting blood sample collection for analysis of insulin, glucose, oxidative and inflammatory markers, an OGTT to assess glucose handling, as well as a FMD procedure to assess endothelial function in response to 6 weeks of either the Placebo or Strawberry treatment. Subjects will be required to visit the Center 4 weeks after the end of their intervention period (Week 10), at which time they will undergo their last anthropometrics and vital sign measurements, a 4 hour OGTT, and the FMD procedure.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Insulin Resistance, Nutritional Disease, Metabolic Disease
Keywords
Insulin Resistant, Dietary Supplements, Nutrition, Antioxidant, Inflammation

7. Study Design

Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
Participant
Allocation
Randomized
Enrollment
45 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Placebo1
Arm Type
Placebo Comparator
Arm Description
Placebo Beverage 1 without fiber
Arm Title
Strawberry
Arm Type
Active Comparator
Arm Description
Strawberry Beverage 20g/BID
Arm Title
Placebo2
Arm Type
Placebo Comparator
Arm Description
Placebo Beverage 2 with Fiber
Intervention Type
Dietary Supplement
Intervention Name(s)
Strawberry
Intervention Description
20g twice per day (BID) in beverage
Intervention Type
Dietary Supplement
Intervention Name(s)
Placebo1
Intervention Description
Placebo Beverage 1 without fiber
Intervention Type
Dietary Supplement
Intervention Name(s)
Placebo2
Intervention Description
Placebo Beverage 2 with Fiber
Primary Outcome Measure Information:
Title
The chronic beneficial effect of polyphenolics from strawberry on impaired insulin signaling in insulin-resistant men and women
Description
Subjects will be randomized to receive either one of beverages, Pbo1, Pbo2 or Str Beverage and consume randomly assigned beverage twice per day with their breakfast and dinner meals for 6 weeks. On visits at Wk0, Wk6, and Wk10, blood will be collected at 0h, and 1h, 2h, 3h and 4h time points following the 75 g glucose load (oral glucose tolerance test) and Flow Mediated Dilation (FMD) procedure will be performed as well.
Time Frame
10 weeks
Secondary Outcome Measure Information:
Title
The chronic beneficial effect of polyphenolics from strawberry on oxidative- and inflammatory-markers in insulin-resistant men and women
Description
Samples of venous blood will be collected for measurement of oxidative and inflammatory markers (hs-CRP levels, LDL oxidation, Interleukin (IL)-6 and other inflammatory molecules, Total antioxidant levels of the blood)
Time Frame
10 Weeks

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
65 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: Must meet ONE or MORE of the criteria (1)-(5) associated with insulin resistance along with all other criteria listed (6)-(9): Blood glucose concentration between140-199 mg/dL at 2hr from OGTT. Elevated fasting glucose (110 mg/dL≤ Fasting blood glucose <126 mg/dL) Elevated fasting insulin (>75th percentile cutoff of 13.13 μU/mL) Insulin resistance defined by the homeostasis model assessment method of insulin resistance (HOMA-IR) (glucose [in millimoles per liter] × insulin [in microunits per milliliter]/22.5) values of at least 2.5. Waist circumference ≥ 110 cm because many epidemiology studies have been shown that waist circumferences may be related to insulin resistance. Nonsmokers Not taking any medications that would interfere with outcomes of the study, i.e. lipid lowering medications, anti-inflammatory drugs, or dietary supplements 18 years of age and older No clinical evidence of cardiovascular, metabolic, respiratory, renal, gastrointestinal or hepatic disease Exclusion Criteria: Pregnant and/or lactating. Allergy or intolerance to strawberries and dairy products. Current regular consumption of strawberries is > 2 servings per day. Fasting blood glucose ≥ 126 mg/dL. Subjects identified with elevated fasting blood glucose levels will be advised to contact their primary care physician for appropriate follow-up care. Taking over the counter antioxidant supplements or other supplements that may interfere with the study procedures or endpoints. Subjects with unusual dietary habits (e.g. pica). Actively losing weight or trying to lose weight (unstable body weight fluctuations of > 5 kg in a 60 day period). Excessive exercisers or trained athletes. Subjects with documented atherosclerotic disease, inflammatory disease, diabetes mellitus, or other systemic diseases. Addicted to drugs and/or alcohol. Medically documented psychiatric or neurological disturbances. Smoker (past smoker may be allowed if cessation is > 2 years).
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Indika Edirisinghe, Ph.D
Organizational Affiliation
Institute for Food Safety and Health
Official's Role
Principal Investigator
First Name & Middle Initial & Last Name & Degree
Britt Burton-Freeman, Ph.D
Organizational Affiliation
Institute for Food Safety and Health
Official's Role
Principal Investigator
Facility Information:
Facility Name
Clinical Nutrition Research Center
City
Chicago
State/Province
Illinois
ZIP/Postal Code
60616
Country
United States

12. IPD Sharing Statement

Citations:
PubMed Identifier
20595645
Citation
Burton-Freeman B, Linares A, Hyson D, Kappagoda T. Strawberry modulates LDL oxidation and postprandial lipemia in response to high-fat meal in overweight hyperlipidemic men and women. J Am Coll Nutr. 2010 Feb;29(1):46-54. doi: 10.1080/07315724.2010.10719816.
Results Reference
result
PubMed Identifier
18816058
Citation
Edirisinghe I, Burton-Freeman B, Varelis P, Kappagoda T. Strawberry extract caused endothelium-dependent relaxation through the activation of PI3 kinase/Akt. J Agric Food Chem. 2008 Oct 22;56(20):9383-90. doi: 10.1021/jf801864t. Epub 2008 Sep 25.
Results Reference
result

Learn more about this trial

Effect of 6-week Strawberry Supplementation on Insulin Action (STR2)

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