Effectiveness of Four Popular Diet Strategies for Weight Loss and Cardiac Risk Reduction

Effectiveness of Four Dietary Treatment Strategies for Metabolic Syndrome: a Prospective Randomized Trial

A single-center randomized trial at an academic medical center in Boston, Mass, of overweight or obese adults with known hypertension, dyslipidemia, or fasting hyperglycemia. Participants were enrolled starting July 18, 2000, and randomized to 4 popular diet groups until January 24, 2002.

Study Overview

• Status: Completed
• Conditions: Obesity; Cardiovascular Disease; Metabolic Syndrome
• Intervention / Treatment: Behavioral: Atkins Diet; Behavioral: Zone Diet; Behavioral: Weight Watchers Diet; Behavioral: Ornish Diet

Detailed Description

Objective: To assess adherence rates and the effectiveness of 4 popular diets (Atkins, Zone, Weight Watchers, and Ornish) for weight loss and cardiac risk factor reduction.

Design, Setting, and Participants: A single-center randomized trial at an academic medical center in Boston, Mass, of overweight or obese adults with known hypertension, dyslipidemia, or fasting hyperglycemia. Participants were enrolled starting July 18, 2000, and randomized to 4 popular diet groups until January 24, 2002.

Intervention: A total of 160 participants were randomly assigned to either Atkins (carbohydrate restriction, n=40), Zone (macronutrient balance, n=40), Weight Watchers (calorie restriction, n=40), or Ornish (fat restriction, n=40) diet groups. After 2 months of maximum effort, participants selected their own levels of dietary adherence.

Main Outcome Measures: One-year changes in baseline weight and cardiac risk factors, and self-selected dietary adherence rates per self-report. Outcome measures included body weight, total cholesterol, LDL-C, HDL-C, triglycerides, hsCRP, insulin, glucose.

• Study Type: Interventional
• Enrollment (Actual): 160
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• BMI 27-42;
• At least one metabolic cardiac risk factor

Exclusion Criteria:

• Age under 18 years;
• Insulin therapy;
• Unstable chronic illness;
• Unwilling to follow dietary advice

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Atkins Diet; Atkins Diet (dietary counseling)	Behavioral: Atkins Diet; Dietary counseling for 1 year
Active Comparator: Zone Diet; Zone Diet (dietary counseling)	Behavioral: Zone Diet; Dietary counseling for 1 year
Active Comparator: Weight Watchers Diet; Weight Watchers Diet (dietary counseling)	Behavioral: Weight Watchers Diet; Dietary counseling for 1 year
Active Comparator: Ornish Diet; Ornish Diet (dietary counseling)	Behavioral: Ornish Diet; Dietary counseling for 1 year

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight Loss	Change from baseline body weight at 1 year, measured in kilograms	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Cholesterol	Change in total cholesterol from baseline at 1 year, measured in mg/dL	1 year
LDL Cholesterol	Change from baseline LDL cholesterol at 1 year, measured in mg/dL	1 year
HDL Cholesterol	Change from baseline HDL cholesterol at 1 year, measured in mg/dL	1 year
Triglycerides	Change from baseline triglycerides at 1 year, measured in mg/dL	1 year
Glucose	Change from baseline glucose at 1 year, measured in mg/dL	1 year
Insulin	Change from baseline insulin at 1 year, measured in microIU/mL	1 year
C-reactive Protein	Change from baseline high-sensitivity CRP at 1 year, measured in mg/L	1 year

Collaborators and Investigators

• Sponsor: Tufts Medical Center
• Investigators: Principal Investigator: Michael L Dansinger, MD, Tufts Medical Center

Publications and helpful links

General Publications

• Dansinger ML, Gleason JA, Griffith JL, Selker HP, Schaefer EJ. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial. JAMA. 2005 Jan 5;293(1):43-53. doi: 10.1001/jama.293.1.43.

Study record dates

Study Major Dates

• Study Start: July 1, 2000
• Primary Completion (Actual): January 1, 2003
• Study Completion (Actual): January 1, 2004

Study Registration Dates

• First Submitted: May 20, 2015
• First Submitted That Met QC Criteria: May 26, 2015
• First Posted (Estimate): May 27, 2015

Study Record Updates

• Last Update Posted (Estimate): October 31, 2016
• Last Update Submitted That Met QC Criteria: September 13, 2016
• Last Verified: September 1, 2016

More Information

Terms related to this study

• Keywords: nutrition; counseling; weight loss; lifestyle; popular diets
• Additional Relevant MeSH Terms: Pathologic Processes; Glucose Metabolism Disorders; Metabolic Diseases; Disease; Insulin Resistance; Hyperinsulinism; Cardiovascular Diseases; Syndrome; Metabolic Syndrome
• Other Study ID Numbers: DANS0001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: Peer-reviewed publication