Effects of Three Dietary Strategies on Body Composition and Metabolic Health in Adults With Overweight or Obesity

Inclusion Criteria: * Adults aged 20-70 years * Body mass index (BMI) ≥ 25 kg/m² (overweight or obesity) * Stable body weight (± 2 kg) in the last 3 months prior to screening * Willingness to follow one of the prescribed dietary interventions for 12 weeks * Ability to attend scheduled follow-up visits and complete study assessments * Provided written informed consent prior to study participation Exclusion Criteria: * Diagnosis of type 1 diabetes, cardiovascular disease, cancer, chronic kidney disease, liver disease, or other serious chronic conditions that could interfere with the intervention * Pregnancy or breastfeeding * Current participation in another clinical trial * History of bariatric surgery or weight-loss program within the past 6 months * Use of medications known to affect body weight, metabolism, or appetite (e.g., glucocorticoids, weight-loss drugs, antipsychotics) * Any food allergy or intolerance that would preclude adherence to the assigned diet * Alcohol or substance abuse * Any condition or circumstance that, in the opinion of the investigators, would make the participant unsuitable for the study