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

Insulin Resistance Clinical Trial

Official title: Effect of 6 Weeks Strawberry Supplementation on Insulin Action and Associated Risk Factors in Insulin Resistant (IR) Subjects (STR2)

Status Completed

Clinical Trial 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.

Clinical Trial 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. ;

Related Conditions & MeSH terms

• Insulin Resistance
• Metabolic Disease
• Metabolic Diseases
• Nutrition Disorders
• Nutritional Disease

• NCT number: NCT01457612
• Study type: Interventional
• Source: Clinical Nutrition Research Center, Illinois Institute of Technology
• Status: Completed
• Phase: N/A
• Start date: October 1, 2011
• Completion date: March 1, 2013