Comparison of Popular Weight Loss Diets
This study will compare the safety and effectiveness of three popular weight loss plans. These plans will be compared with the USDA Dietary Guidelines.
Behavioral: Atkins diet (extremely low carbohydrate)
Behavioral: Zone diet (low carbohydrate, high protein)
Behavioral: Ornish diet (very low fat)
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind
Primary Purpose: Treatment
|Official Title:||Benefits & Risks of Popular Weight Loss Diets|
- Weight; measured at each study visit
- Percent body fat; measured at each study visit
- 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
|Study Start Date:||July 2002|
|Estimated Study Completion Date:||June 2004|
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.
|United States, California|
|Stanford Prevention Research Center|
|Stanford, California, United States, 94305|
|Principal Investigator:||Christopher D. Gardner, PhD||Stanford University|