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Comparison of Popular Weight Loss Diets

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ClinicalTrials.gov Identifier: NCT00079573
Recruitment Status : Completed
First Posted : March 10, 2004
Last Update Posted : August 18, 2006
Community Foundation of Southeastern Michigan
Information provided by:
National Center for Complementary and Integrative Health (NCCIH)

Tracking Information
First Submitted Date  ICMJE March 9, 2004
First Posted Date  ICMJE March 10, 2004
Last Update Posted Date August 18, 2006
Study Start Date  ICMJE July 2002
Primary Completion Date Not Provided
Current Primary Outcome Measures  ICMJE
 (submitted: September 6, 2005)
  • Weight; measured at each study visit
  • Percent body fat; measured at each study visit
Original Primary Outcome Measures  ICMJE Not Provided
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: September 6, 2005)
  • Blood lipids (cholesterol, triglycerides); measured at each study visit
  • Fasting insulin and glucose; measured at each study visit
  • Behavioral variables; measured at each study visit
Original Secondary Outcome Measures  ICMJE Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Comparison of Popular Weight Loss Diets
Official Title  ICMJE Benefits & Risks of Popular Weight Loss Diets
Brief Summary This study will compare the safety and effectiveness of three popular weight loss plans. These plans will be compared with the USDA Dietary Guidelines.
Detailed Description

Obesity is the single most significant, nutrition-related health issue of the new millennium. Several "medical experts" have designed and promoted weight loss diets that dramatically differ from one another and from the USDA Dietary Guidelines. These diets have gained surprisingly widespread and persistent popularity among Americans despite the lack of evidence supporting their claims. This clinical trial will provide preliminary feasibility data for a full-scale study that will examine health outcomes (e.g., benefits, risks, success) of three popular weight loss diets. The study will investigate behavioral and physiological factors that influence adherence and retention to these diet plans.

Overweight women will be randomly assigned to one of four diets for 1 year: Atkins (extremely low carbohydrate), Zone (low carbohydrate, high protein), Ornish (very low fat), or USDA/Food Pyramid (high carbohydrate/moderate-low fat). Behavioral and physiological data will be collected. Participants attend study visits at baseline, 8 weeks, 6 months, and 1 year. At these visits, measurements will include that will include weight and blood pressure measurements and blood tests. Participants will be asked to complete ten questionnaires over the course of the study to assess behavior and appetite. Participants will also undergo a DEXA scan to assess body composition.

Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 2
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single
Primary Purpose: Treatment
Condition  ICMJE Obesity
Intervention  ICMJE
  • Behavioral: Atkins diet (extremely low carbohydrate)
  • Behavioral: Zone diet (low carbohydrate, high protein)
  • Behavioral: Ornish diet (very low fat)
Study Arms  ICMJE Not Provided
Publications * Gardner CD, Kiazand A, Alhassan S, Kim S, Stafford RS, Balise RR, Kraemer HC, King AC. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77. Erratum in: JAMA. 2007 Jul 11;298(2):178.

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Enrollment  ICMJE
 (submitted: August 2, 2006)
Original Enrollment  ICMJE
 (submitted: June 23, 2005)
Study Completion Date  ICMJE June 2004
Primary Completion Date Not Provided
Eligibility Criteria  ICMJE

Inclusion Criteria

  • Body mass index (BMI) between 27 and 40 kg/m2
  • Weight stable for last 2 months
  • Not actively on a weight loss plan
  • No plans to move from the area over the next 2 years
  • Willing to accept random assignment

Exclusion Criteria

  • Pregnant or breastfeeding
  • Within 6 months of giving birth or planning to become pregnant in the next 2 years
  • Diabetes (type 1 or 2) or history of gestational diabetes
  • Renal or liver disease, active neoplasms, or recent myocardial infarction
  • Hyper- or hypothyroidism
  • Lipid lowering medications or medications known to affect weight/energy expenditure
  • Excessive alcohol intake (self-reported, > 3 drinks/day)
  • Postmenopausal, including surgical menopause
  • Currently under psychiatric care or severely clinically depressed (> 17 on Beck Inventory)
Sex/Gender  ICMJE
Sexes Eligible for Study: Female
Ages  ICMJE 30 Years to 50 Years   (Adult)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT00079573
Other Study ID Numbers  ICMJE R21AT001098-01A1( U.S. NIH Grant/Contract )
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Current Responsible Party Not Provided
Original Responsible Party Same as current
Current Study Sponsor  ICMJE National Center for Complementary and Integrative Health (NCCIH)
Original Study Sponsor  ICMJE Same as current
Collaborators  ICMJE Community Foundation of Southeastern Michigan
Investigators  ICMJE
Principal Investigator: Christopher D. Gardner, PhD Stanford University
PRS Account National Center for Complementary and Integrative Health (NCCIH)
Verification Date August 2006

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP