Dietary Protein and Insulin Sensitivity Study

This study has been completed.
Sponsor:
Collaborator:
Dairy Management Inc.
Information provided by:
Children's Hospital & Research Center Oakland
ClinicalTrials.gov Identifier:
NCT00508937
First received: July 26, 2007
Last updated: October 4, 2011
Last verified: October 2011
  Purpose

The overall objective of the Dietary Protein and Insulin Sensitivity Study is to test the hypothesis that increased protein in a diet with reduced carbohydrate (35% energy) can ameliorate insulin resistance in the absence of weight loss, and that this effect is independent of saturated fat content. Moreover, we will test whether such diets result in beneficial changes in total LDL cholesterol, small, dense LDL, and HDL cholesterol that are also independent of saturated fat intake.


Condition Intervention
Insulin Resistance
Type 2 Diabetes
Metabolic Syndrome
Cardiovascular Disease
Dyslipidemia
Other: Diet

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Investigator)
Primary Purpose: Prevention
Official Title: The Effects of Increased Dietary Protein Intake on Insulin Sensitivity in Stable Weight Individuals, Independent of Dietary Content of Carbohydrate and Saturated Fat

Resource links provided by NLM:


Further study details as provided by Children's Hospital & Research Center Oakland:

Primary Outcome Measures:
  • Insulin Sensitivity by Frequently Sampled Intravenous Glucose Tolerance test [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • Total Cholesterol [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • LDL Cholesterol [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • HDL Cholesterol [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • Triglycerides [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • LDL peak particle size [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • LDL subclasses [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Apolipoprotein B [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]
  • Apolipoprotein A1 [ Time Frame: 4wks and 8wks ] [ Designated as safety issue: No ]

Estimated Enrollment: 250
Study Start Date: February 2007
Study Completion Date: December 2009
Primary Completion Date: November 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1 Other: Diet
15% protein, 55% carbohydrate, 30% fat (7% saturated, 7% polyunsaturated)
Experimental: 2 Other: Diet
20% protein, 35% carbohydrate, 45% fat (7% saturated, 7% polyunsaturated)
Experimental: 3 Other: Diet
20% protein, 35% carbohydrate, 45% fat (15% saturated, 7% polyunsaturated)
Experimental: 4 Other: Diet
30% protein, 35% carbohydrate, 35% fat (7% saturated, 7% polyunsaturated)
Experimental: 5 Other: Diet
30% protein, 35% carbohydrate, 35% fat (15% saturated, 7% polyunsaturated)

Detailed Description:

Insulin resistance is a major metabolic disturbance associated with excess adiposity that contributes to atherogenic dyslipidemia and predisposes to both cardiovascular disease and type 2 diabetes mellitus. The effects on insulin resistance of changes in dietary macronutrient composition in the absence of weight loss are poorly understood. To better understand these effects, we will study men and women with insulin resistance after 4 weeks on a basal diet (15% protein, 55% carbohydrate, 30% fat) and 4 weeks after random assignment to the basal diet or one of 4 diets with 35% carbohydrate and either 20% or 30% protein, and either 7% or 15% saturated fat. At the end of each dietary period (4 weeks and 8 weeks), we will draw a blood sample for detailed metabolic measurements and measure insulin sensitivity by the frequently sampled intravenous glucose tolerance test (FSIGT) method. In addition to insulin resistance, we will assess the effect of dietary composition on parameters of atherogenic dyslipidemia.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Body mass index (BMI) ≥ 27 and ≤ 40 kg/m2
  • HOMA-IR ≥ 2.5
  • Non-smoking
  • Total cholesterol and LDL cholesterol <95th percentile for sex and age
  • Fasting triglycerides < 500mg/dl
  • Fasting blood sugar < 126
  • Urinary microalbumin < 30 mg/L
  • Normal thyroid stimulating hormone levels
  • Hematocrit ≥ 36%
  • Blood pressure < 150/90
  • At least 3 months of a weight-stable state (± 5 lbs) prior to the study. During the study, subjects will be required to maintain their body weight within ± 3% (up to a maximum change of 5 lbs) of their initial weight over the course of any consecutive two weeks after the second week of baseline diet or during the last week of each diet phase

Exclusion Criteria:

  • History of coronary heart disease, cerebrovascular disease, peripheral vascular disease, bleeding disorder, liver or renal disease, diabetes, lung disease, HIV, or cancer (other than skin cancer) in the last 5 years
  • Use of drugs known to affect lipid metabolism or insulin resistance, hormones, or the blood thinning agent, warfarin
  • Use of alcohol or dietary supplements during the study
  • Pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00508937

Locations
United States, California
Cholesterol Research Center
Berkeley, California, United States, 94705
San Francisco General Hospital
San Francisco, California, United States, 94110
Sponsors and Collaborators
Children's Hospital & Research Center Oakland
Dairy Management Inc.
Investigators
Principal Investigator: Ronald M Krauss, M.D. Children's Hospital & Research Center Oakland
  More Information

Additional Information:
No publications provided

Responsible Party: Ronald M. Krauss, M.D., Children's Hospital Oakland Research Institute
ClinicalTrials.gov Identifier: NCT00508937     History of Changes
Other Study ID Numbers: MM3717
Study First Received: July 26, 2007
Last Updated: October 4, 2011
Health Authority: United States: Institutional Review Board

Keywords provided by Children's Hospital & Research Center Oakland:
Diet
Protein
Glucose
Insulin
Cholesterol
Triglycerides
LDL subclasses

Additional relevant MeSH terms:
Diabetes Mellitus, Type 2
Cardiovascular Diseases
Metabolic Syndrome X
Insulin Resistance
Dyslipidemias
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Hyperinsulinism
Lipid Metabolism Disorders
Insulin
Hypoglycemic Agents
Physiological Effects of Drugs
Pharmacologic Actions

ClinicalTrials.gov processed this record on September 18, 2014