The WORLD (Weight Optimization: Revamping Lifestyles Using the Dietary Guidelines) Study - Developing, Implementing, and Testing an Education Program

Not Applicable

Completed

• Conditions: Obesity; Cardiovascular Disease
• Interventions: Behavioral: Moderate-fat; Behavioral: Lower-fat

• Registration Number: NCT00847574
• Lead Sponsor: Penn State University

Brief Summary

The WORLD study is a single-center, year-long randomized controlled trial in free-living women. Participants were randomly assigned to follow either a lower-fat (LF) diet or a moderate-fat (MF) diet for weight management in a parallel-arm design. The two phases of the study were a weight-loss phase (phase 1) and a weight-maintenance phase (phase 2) (Figure 1). During phase 1, months 1 through 4, participants consumed a hypo-caloric diet consistent with the 2005 Dietary Guidelines in the free-living environment. During phase 2, months 5 through 12, participants shifted into weight maintenance. It was hypothesized that a weight-loss intervention at the extremes of dietary fat recommendations of the 2005 Dietary Guidelines would be equally effective for weight loss while achieving comparable nutrient adequacy. Also, Overall, the lower-fat and moderate-fat diets would both be nutritionally adequate, based on the Healthy Eating Index.

Detailed Description

Not available

Study Timeline

• Study Start: 2006-03
• Primary Completion: 2008-06
• Study First Submitted: 2009-02-18
• Study First Submitted QC: 2009-02-18
• Study First Posted: 2009-02-19
• Study Completion: 2010-12
• Status Verified: 2023-08
• Last Update Submitted: 2023-08-15
• Last Update Posted: 2023-08-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 101

Inclusion Criteria

• 21-50 years
• BMI: 25-39.9 kg/m2
• LDL-C: 100-189.9 mg/dL

Exclusion Criteria

• Triglycerides > 350 mg/dL
• History of myocardial infarction, stroke, diabetes mellitus, liver disease, kidney disease, and thyroid disease
• High alcohol consumption (<14 drinks/week)
• Use of medication or supplements for lowering blood lipid levels (i.e., statin, fibrates, psyllium, fish oil capsules, soy lecithin, phytoestrogens)
• Lactating, pregnant, or wanting to become pregnant during the study
• Weight loss or gain ≥ 10% body weight in the previous 6 months
• Eating Attitudes Test-26 score > 20
• Beck Depression Inventory-II score ≥ 29
• Gormally Cognitive Factors Related to Binge Eating Scale score > 30
• Physical Activity Readiness Questionnaire score > 2

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Moderate-fat	Moderate-fat	35% of calories from fat
Lower-fat	Lower-fat	20% of calories from fat

Primary Outcome Measures

Name	Time	Method
Body weight	Baseline, month 4, month 8, month 12

Secondary Outcome Measures

Name	Time	Method
Insulin	Baseline, month 4, month 8, month 12
Glucose	Baseline, month 4, month 8, month 12
Fitness via VO2max	Baseline, month 4, month 12
Lipid Profile	Baseline, month 4, month 8, month 12
Body composition	Baseline, month 4, month 12
Dietary intake	Baseline, month 4, month 12
C-reactive protein	Baseline, month 4, month 8, month 12
Cognitive-behavioral measures	Baseline, month 4, month 8, month 12

Trial Locations

Locations (1)

Penn State University; 🇺🇸 University Park, Pennsylvania, United States