Cardiovascular Disease, Obesity
Conditions
Keywords
Weight loss, Weight maintenance, Weight management, Cardiovascular disease risk, Dietary Guidelines, Diet and exercise, Prevention
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.
Interventions
BEHAVIORALModerate-fat
35% of calories from fat
BEHAVIORALLower-fat
20% of calories from fat
Sponsors
United States Department of Agriculture (USDA)
Penn State University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
21 Years to 50 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Body weight | Baseline, month 4, month 8, month 12 |
Secondary
| Measure | Time frame |
|---|---|
| Glucose | Baseline, month 4, month 8, month 12 |
| Insulin | Baseline, month 4, month 8, month 12 |
| C-reactive protein | Baseline, month 4, month 8, month 12 |
| Lipid Profile | Baseline, month 4, month 8, month 12 |
| Body composition | Baseline, month 4, month 12 |
| Fitness via VO2max | Baseline, month 4, month 12 |
| Cognitive-behavioral measures | Baseline, month 4, month 8, month 12 |
| Dietary intake | Baseline, month 4, month 12 |
Countries
United States
Outcome results
None listed