Long Term Weight Loss Diets and Obesity Indices: Results of a Network Meta-Analysis

Jana Jabbour; Yasmin Rihawi; Assem M Khamis; Layal Ghamlouche; Bayan Tabban; Gloria Safadi; Nour Hammad; Ruba Hadla; Marwa Zeidan; Dana Andari; Riwa Nour Azar; Nadine Nasser; Marlene Chakhtoura

doi:10.3389/fnut.2022.821096

Long Term Weight Loss Diets and Obesity Indices: Results of a Network Meta-Analysis

Front Nutr. 2022 Apr 5:9:821096. doi: 10.3389/fnut.2022.821096. eCollection 2022.

Authors

Jana Jabbour^{1

2}, Yasmin Rihawi², Assem M Khamis³, Layal Ghamlouche^{2

4}, Bayan Tabban², Gloria Safadi⁵, Nour Hammad^{2

6}, Ruba Hadla⁷, Marwa Zeidan⁸, Dana Andari^{8

9}, Riwa Nour Azar^{2

10}, Nadine Nasser^{2

11}, Marlene Chakhtoura¹²

Affiliations

¹ Nutrition Department, School of Health Sciences, Modern University for Business and Sciences, Beirut, Lebanon.
² Department of Clinical Nutrition, American University of Beirut Medical Center, Beirut, Lebanon.
³ York Medical School, University of Hull, York, United Kingdom.
⁴ Research & Programmes Department, Qualisus Consulting, Byblos, Lebanon.
⁵ Center for Research on Population and Health, Faculty of Health Sciences, American University of Beirut, Beirut, Lebanon.
⁶ Duke Global Health Institute, Duke University, Durham, NC, United States.
⁷ Department of Health Management and Policy, Faculty of Health Sciences, American University of Beirut, Beirut, Lebanon.
⁸ Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
⁹ Department of Nutrition and Dietetics, Faculty of Health Sciences, Beirut Arab University, Beirut, Lebanon.
¹⁰ The European School of Management and Technology, Berlin, Germany.
¹¹ Access to Nutrition Initiative, Utrecht, Netherlands.
¹² Calcium Metabolism and Osteoporosis Program, WHO Collaborating Center for Metabolic Bone Disorders, American University of Beirut Medical Center, Beirut, Lebanon.

Abstract

Background: Scientists have been investigating efficient interventions to prevent and manage obesity. This network meta-analysis (NMA) compared the effect of different diets [moderate macronutrients (MMs), low fat/high carbohydrate (LFHC), high fat/low carbohydrate (HFLC), and usual diet (UD)] on weight, body mass index (BMI), and waist circumference (WC) changes at ≥12 months.

Methods: We searched Medline, Embase, PubMed databases, and the Cochrane Library. We systematically assessed randomized controlled trials (RCTs) evaluating dietary interventions on adults (mean BMI ≥ 25 kg/m²) receiving active dietary counseling for ≥12 months. We pooled the data using a random-effect NMA. We assessed the quality of the included RCTs using the Cochrane risk of bias (ROB) tool.

Results: We included 36 trials, 14 of which compared HFLC with MM diets. Compared with UD, all diets were associated with a significant weight loss (WL) at ≥12 months, HFLC [mean difference in kg (95% CI): -5.5 (-7.6; -3.4)], LFHC [-5.0 (-7.1; -2.9)] and MM [-4.7 (-6.8; -2.7)]. HFLC, compared with MM diet, was associated with a slightly higher WL (of -0.77 kg) and drop in BMI (of -0.36 kg/m²), while no significant difference was detected in other dietary comparisons. WC was lower with all diets compared to UD, with no significant difference across specific diets. There was no significant interaction of the results with the pre-specified sub-groups. The ROB was moderate to high, mostly related to unclear allocation concealment, high dropout rate and unclear or lack of blinding of participants, providers, and outcome assessors.

Conclusion: Dietary interventions extending over ≥12 months are superior to UD in inducing weight, BMI and WC loss. HFLC might be associated with a slightly higher WL compared with MM diets.

Systematic trial registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=103116, PROSPERO (CRD42018103116).

Keywords: Acceptable Macronutrient Distribution Ranges (AMDR); body mass index (BMI); diet; obesity; waist circumference; weight loss.

Publication types

Systematic Review