The effectiveness of fasting regimens on serum levels of some major weight regulating hormones: a GRADE-assessed systematic review and meta-analysis in randomized controlled trial

A current investigation was performed to review and summarize the results of randomized clinical trials (RCTs) studies that have assessed the effectiveness of fasting regimens (FRs) including intermittent fasting (IF), time-restricted feeding (TRF), alternate day fasting (ADF) and fasting-mimicking diet (FMD) on some weight regulation hormones included; leptin, adiponectin, ghrelin, and resistin in healthy, overweight and obese adults recently. Four databases have been reviewed until June 2024 using keywords related to the subject of the study. Overall, 16 documents were considered in this study. Based on Pooled effect sizes, the FRs marginal significantly increased the level of adiponectin (weighted mean differences (WMD): 0.41 mu g/ml, 95% confidence interval (CI): - 0.07 to 0.89, P: 0.09) and also significantly decreased the level of leptin (WMD: - 2.65 ng/ml, 95% CI: - 3.86 to - 1.44, p < 0.001) and ghrelin (WMD: - 0.57 ng/ml, 95% CI: - 1.01 to - 0.03, P: 0.01). There was no significant effect of this regimen approach on resistin levels. In general, according to this evaluation, FRs have a beneficial impact on weight-regulating hormone levels, still the long-term effects of these dietary approaches should also be evaluated in future studies.