» Articles » PMID: 39929932

Fasting Appetite-related Gut Hormone Responses After Weight Loss Induced by Calorie Restriction, Exercise, or Both in People with Overweight or Obesity: a Meta-analysis

Overview
Date 2025 Feb 10
PMID 39929932
Authors
Affiliations
Soon will be listed here.
Abstract

Objectives: Altered appetite-related gut hormone concentrations may reflect a physiological adaptation facilitating weight regain after weight loss. This review investigates hormonal changes after weight loss achieved through calorie restriction (CR), exercise (EX), or both combined (CREX).

Methods: A systematic search of PubMed (MEDLINE), EMBASE, SPORTDiscus, Cochrane Library, Web of Science, and ClinicalTrials.gov was conducted to identify randomised controlled trials (RCTs) and non-RCTs reporting in a fasting state either pre- and post-intervention appetite-related hormone concentrations or the changes therein after weight loss. The hormones examined were ghrelin, peptide tyrosine tyrosine (PYY), glucagon-like peptide -1 (GLP-1), and cholecystokinin (CCK), in their total and/or active form. Standardised mean differences (SMD) were extracted as the effect size.

Results: 127 studies were identified: 19 RCTs, 108 non-RCTs, 1305 and 4725 participants, respectively. In response to weight loss induced by CR, EX or CREX, the meta-analysis revealed an increase in total ghrelin from both RCTs (SMD: 0.55, 95% CI: 0.07-1.04) and non-RCTs (SMD: 0.24, 95% CI: 0.14-0.35). A decrease in acylated ghrelin was identified for RCTs (SMD: -0.58, 95% CI: -1.09 to -0.06) but an increase was observed for non-RCTs (SMD: 0.15, 95% CI: 0.03 to 0.27). Findings also revealed a decrease in PYY (total PYY: SMD: -0.17, 95%CI: -0.28 to -0.06; PYY: SMD: -0.17, 95%CI: -0.32 to -0.02) and active GLP-1 (SMD: -0.16, 95% CI: -0.28 to -0.05) from non-RCTs. Changes in hormones did not differ among the three interventions when controlling for weight loss. Meta-regression indicated that greater weight loss was associated with a greater increase in total ghrelin.

Conclusions: Weight loss induced by CR, EX, or CREX elicits an increase in total ghrelin, but varied responses in other appetite-related hormones. The extent of weight loss influences changes in appetite-related gut hormone concentrations.

References
1.
Sarma S, Sockalingam S, Dash S . Obesity as a multisystem disease: Trends in obesity rates and obesity-related complications. Diabetes Obes Metab. 2021; 23 Suppl 1:3-16. DOI: 10.1111/dom.14290. View

2.
Anderson J, Konz E, Frederich R, Wood C . Long-term weight-loss maintenance: a meta-analysis of US studies. Am J Clin Nutr. 2001; 74(5):579-84. DOI: 10.1093/ajcn/74.5.579. View

3.
Busetto L, Bettini S, Makaronidis J, Roberts C, Halford J, Batterham R . Mechanisms of weight regain. Eur J Intern Med. 2021; 93:3-7. DOI: 10.1016/j.ejim.2021.01.002. View

4.
Abdalla M . Ghrelin - Physiological Functions and Regulation. Eur Endocrinol. 2018; 11(2):90-95. PMC: 5819073. DOI: 10.17925/EE.2015.11.02.90. View

5.
Tschop M, Smiley D, Heiman M . Ghrelin induces adiposity in rodents. Nature. 2000; 407(6806):908-13. DOI: 10.1038/35038090. View