Comparison of Popular Weight Loss Diets

Phase 2

Completed

• Conditions: Obesity

• Registration Number: NCT00079573
• Lead Sponsor: National Center for Complementary and Integrative Health (NCCIH)

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 Timeline

• Study Start: 2002-07
• Study First Submitted: 2004-03-09
• Study First Submitted QC: 2004-03-09
• Study First Posted: 2004-03-10
• Study Completion: 2004-06
• Status Verified: 2006-08
• Last Update Submitted: 2006-08-16
• Last Update Posted: 2006-08-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 300

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Weight; measured at each study visit
Percent body fat; measured at each study visit

Secondary Outcome Measures

Name	Time	Method
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

Trial Locations

Locations (1)

Stanford Prevention Research Center; 🇺🇸 Stanford, California, United States