Comparison of Two Different Diets on Health Outcomes

Metabolic Syndrome X Clinical Trial

Official title:

Effect of a Low-Carbohydrate and High-Carbohydrate, High-Fiber Diet on Insulin Sensitivity and Risk Markers for Cardiovascular Disease in Men and Women With the Metabolic Syndrome

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT00269646
• Other study ID #: HIC11487
• Status: Active, not recruiting
• Phase: N/A
• First received: December 21, 2005
• Last updated: February 16, 2009
• Start date: November 2004
• Est. completion date: August 2009

Study information

• Verified date: February 2009
• Source: University of Virginia
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to compare the effects of a low-carbohydrate diet and a high-carbohydrate, high-fiber diet, on insulin sensitivity and blood chemicals considered risk markers for heart disease, in persons with the metabolic syndrome.

Our primary hypothesis is that the ad libitum high-carbohydrate, high-fiber diet will significantly improve insulin sensitivity, whereas the ad libitum low-carbohydrate, low-fiber diet will not.

Description:

Low-carbohydrate eating is becoming perceived as more than just a weight loss diet, but rather a means to improve health. Several studies have been published suggesting that low-carbohydrate diets may be preferable to low-fat diets for weight loss and in terms of some health markers. On the other hand, considerable evidence suggests that low-carbohydrate diets, high in fat, are associated with a number of adverse health outcomes. The health benefits of high-carbohydrate, high-fiber diets have also been demonstrated. This study is designed to assess the differences between the two different dietary strategies in terms of a number of health outcomes. Participants will consume, in random order, a non-calorie-restricted low-carbohydrate and a non-calorie-restricted high-carbohydrate, high-fiber diet for one month, with a 4-6 week washout period in between.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 24
• Est. completion date: August 2009
• Est. primary completion date: February 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 64 Years

Eligibility

Inclusion Criteria:

1. Subjects must meet the criteria of the metabolic syndrome, which is defined as having three or more of the following:

• Waist circumference: >94 cm for males; >80 cm for females

• Blood Pressure: >130/85 mmHg

• HDL-Chol (mg/dl): <50 women; <40 men)

• Triglycerides (mg/dl): >150

• Glucose (mg/dl): >100 2. Subjects must meet age requirement 3. Subjects must be nonsmokers 4. Subjects must be willing to provide written consent 5. Subjects must be willing to pick-up up meals at the GCRC and return uneaten food 6. Have no food allergies 7. Subjects must not be currently following any particular diet, and must not have intentionally lost weight by dieting during the previous 3 months 8. Subjects must not be taking nutritional supplements other than a daily multivitamin

9. Subjects must be willing to maintain current physical activity routine, which cannot exceed the equivalent of > 30 minutes per day of moderate-intensity activity

10. Blood hematocrit must be at least 40 for men and 36 for women.

Exclusion Criteria:

1. Does not meet the criteria for the metabolic syndrome 2. Does not meet age requirement

3. Smoker 4. Pregnancy 5. Food allergies 6. Unwillingness to provide written consent 7. Personal history of cardiovascular disease, including prior myocardial infarction, angioplasty, or bypass surgery 8. Known cardiovascular or metabolic diseases (e.g., diabetes) 9. Currently using medications to control blood pressure, lipids, or glucose 10. Currently on a diet or has attempted weight loss by dieting during the past 3 months 11. Currently taking nutritional supplements other than a daily multivitamin 12. Currently exercising more than the equivalent of 30 minutes/day of moderate-intensity physical activity 13. Currently on oral contraceptives 14. Hematocrit below 40 for men or below 36 for women 15. Baseline systolic blood pressure below 100 mmHg

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Single Blind (Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Cardiovascular Diseases
• Metabolic Syndrome X

Intervention

Behavioral:
• Low-carbohydrate and high-carbohydrate diets
Each subject will consume two different ad libitum diets, each for four weeks, with a 4-week washout period inbetween each diet.

Locations

Country	Name	City	State
United States	University of Virginia General Clinical Research Center	Charlottesville	Virginia

Sponsors (1)

Lead Sponsor	Collaborator
University of Virginia

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	insulin sensitivity		before and after one month on each diet	No
Secondary	Total and LDL-cholesterol		before and after one month on each diet	No
Secondary	C-reactive protein		before and after one month on each diet	No
Secondary	Homocysteine		before and after one month on each diet	No
Secondary	Fibrinogen		before and after one month on each diet	No
Secondary	Cytokines IL-1, IL-2, IL-6 and TNF-alpha		before and after one month on each diet	No
Secondary	Leukocyte adhesion molecules		before and after one month on each diet	No
Secondary	Flow-mediated dilation		before and after one month on each diet	No