Dietary Modification as a Strategy for Weight Loss and Metabolic Parameter Improvement in Obesity: A Systematic Review

Introduction: Obesity is linked to higher risks of metabolic diseases such as dyslipidemia, type 2 diabetes, and cardiovascular disease, and it continues to be a significant global health concern. Dietary modification has become one of the management options that may be used to reduce weight and improve metabolic outcomes. The relative efficacy of various fat-modified dietary therapies is still unknown, though. The purpose of this systematic review was to assess how dietary changes affected the body weight and lipid profiles of obese people. Methods: Following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, literature searches were conducted in PubMed, Google Scholar, and Crossref, yielding 886 records. After screening, 48 full-text articles were assessed, with 23 randomized controlled trials (RCTs) meeting the inclusion criteria. Methodological quality was evaluated using the Joanna Briggs Institute (JBI) Critical Appraisal Randomized Controlled Trial Checklist. Data were synthesized narratively. Results: Most studies (19/23) reported significant weight loss, and 13 out of 17 studies demonstrated improvements in lipid parameters, particularly in triglycerides, total cholesterol, and low-density lipoprotein (LDL) levels. High protein, low carbohydrate, high fat, low fat, and nut-enriched diets showed the most consistent metabolic benefits. Discussion: Dietary modifications in general have consistently shown benefits for weight reduction and metabolic profile improvement, including lipid parameters, although variations across intervention types highlight the need for more standardized protocols. Conclusion: Based on the 23 selected studies, dietary modification interventions, particularly those rich in protein and unsaturated fats, appear to be effective and potentially sustainable strategies for obesity management and metabolic improvement.