The influence of fasting and energy-restricted diets on leptin and adiponectin levels in humans: A systematic review and meta-analysis

Hamed Varkaneh Kord; Grant M Tinsley; Heitor O Santos; Hamid Zand; Ali Nazary; Somaye Fatahi; Zeinab Mokhtari; Ammar Salehi-Sahlabadi; Shing Cheng Tan; Jamal Rahmani; Mihnea-Alexandru Gaman; Brijesh Sathian; Amir Sadeghi; Behzad Hatami; Samira Soltanieh; Shahin Aghamiri; Hiba Bawadi; Azita Hekmatdoost

doi:10.1016/j.clnu.2020.10.034

The influence of fasting and energy-restricted diets on leptin and adiponectin levels in humans: A systematic review and meta-analysis

Clin Nutr. 2021 Apr;40(4):1811-1821. doi: 10.1016/j.clnu.2020.10.034. Epub 2020 Oct 24.

Authors

Hamed Varkaneh Kord¹, Grant M Tinsley², Heitor O Santos³, Hamid Zand⁴, Ali Nazary⁵, Somaye Fatahi⁶, Zeinab Mokhtari⁷, Ammar Salehi-Sahlabadi¹, Shing Cheng Tan⁸, Jamal Rahmani¹, Mihnea-Alexandru Gaman⁹, Brijesh Sathian¹⁰, Amir Sadeghi¹¹, Behzad Hatami¹¹, Samira Soltanieh¹, Shahin Aghamiri¹², Hiba Bawadi¹³, Azita Hekmatdoost¹⁴

Affiliations

¹ Department of Clinical Nutrition and Dietetics, National Nutrition and Food Technology Research Institute, Faculty of Nutrition Science and Food Technology, Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
² Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, United States.
³ School of Medicine, Federal University of Uberlandia (UFU), Uberlandia, Minas Gerais, Brazil.
⁴ Department of Cellular and Molecular Nutrition, National Nutrition and Food Technology Research Institute, Faculty of Nutrition Science and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
⁵ Department of Cellular and Molecular, Nutrition School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran.
⁶ Student Research Committee, Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
⁷ Food Security Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
⁸ UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
⁹ "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania; Center of Hematology and Bone Marrow Transplantation, Fundeni Clinical Institute, Bucharest, Romania.
¹⁰ Department of Geriatrics and Long Term Care, Rumailah Hospital, Doha, Qatar.
¹¹ Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
¹² Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
¹³ College of Health Sciences, QU-Health, Qatar University, Doha, Qatar.
¹⁴ Department of Clinical Nutrition and Dietetics, National Nutrition and Food Technology Research Institute, Faculty of Nutrition Science and Food Technology, Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: a_hekmat2000@yahoo.com.

PMID: 33158587
DOI: 10.1016/j.clnu.2020.10.034

Abstract

Background & aims: Fasting and energy-restricted diets have been evaluated in several studies as a means of improving cardiometabolic biomarkers related to body fat loss. However, further investigation is required to understand potential alterations of leptin and adiponectin concentrations. Thus, we performed a systematic review and meta-analysis to derive a more precise estimate of the influence of fasting and energy-restricted diets on leptin and adiponectin levels in humans, as well as to detect potential sources of heterogeneity in the available literature.

Methods: A comprehensive systematic search was performed in Web of Science, PubMed/MEDLINE, Cochrane, SCOPUS and Embase from inception until June 2019. All clinical trials investigating the effects of fasting and energy-restricted diets on leptin and adiponectin in adults were included.

Results: Twelve studies containing 17 arms and a total of 495 individuals (intervention = 249, control = 246) reported changes in serum leptin concentrations, and 10 studies containing 12 arms with a total of 438 individuals (intervention = 222, control = 216) reported changes in serum adiponectin concentrations. The combined effect sizes suggested a significant effect of fasting and energy-restricted diets on leptin concentrations (WMD: -3.690 ng/ml, 95% CI: -5.190, -2.190, p ≤ 0.001; I² = 84.9%). However, no significant effect of fasting and energy-restricted diets on adiponectin concentrations was found (WMD: -159.520 ng/ml, 95% CI: -689.491, 370.451, p = 0.555; I² = 74.2%). Stratified analyses showed that energy-restricted regimens significantly increased adiponectin (WMD: 554.129 ng/ml, 95% CI: 150.295, 957.964; I² = 0.0%). In addition, subsequent subgroup analyses revealed that energy restriction, to ≤50% normal required daily energy intake, resulted in significantly reduced concentrations of leptin (WMD: -4.199 ng/ml, 95% CI: -7.279, -1.118; I² = 83.9%) and significantly increased concentrations of adiponectin (WMD: 524.04 ng/ml, 95% CI: 115.618, 932.469: I² = 0.0%).

Conclusion: Fasting and energy-restricted diets elicit significant reductions in serum leptin concentrations. Increases in adiponectin may also be observed when energy intake is ≤50% of normal requirements, although limited data preclude definitive conclusions on this point.

Keywords: Adiponectin; Diets; Energy-restricting; Fasting; Leptin.

Publication types

Meta-Analysis
Research Support, Non-U.S. Gov't
Systematic Review

MeSH terms

Adiponectin / blood*
Caloric Restriction / methods*
Energy Intake / physiology*
Fasting / blood*
Fasting / physiology
Humans
Leptin / blood*

Substances

Adiponectin
Leptin