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.
Age range
21 Years – 50 Years
Sex
FEMALE
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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Body weight
Timeframe: Baseline, month 4, month 8, month 12