Effect of early time-restricted feeding on the metabolic profile of adults with excess weight: A systematic review with meta-analysis

Background & aims: Time-restricted feeding (TRF) studies have been summarized in previous systematic reviews, but these were not specific for individuals with excess weight and studies involving early timerestricted feeding (eTRF). This meta-analysis aimed to evaluate the effect of eTRF on the metabolic profile of adults with excess weight. Methods: Data were extracted from MEDLINE, CENTRAL, LILACS, Web of Science, ClinicalTrials.gov, OpenGrey.eu, Greylit, and by manual search. Randomized controlled trials in which the participants were older than 18 years, with a body mass index greater than 25 kg/m2 and that were allocated in an intervention with eTRF were included. The studies should have assessed any of the following outcomes from the metabolic profile: resting metabolic rate, triacylglycerol, total cholesterol, HDL-cholesterol, and LDL-cholesterol, fasting blood glucose, insulin, HOMA-IR, C-reactive protein, Interleukin-6, cortisol, leptin, Ghrelin, Peptide YY and glucagon-like peptide, hemodynamic parameters, and appetite. The risk of bias was assessed using the Cochrane collaboration tool. Publication bias was examined with a funnel plot and Egger's test. GRADE was used to assess the overall quality of evidence. Results: Ten articles from nine randomized clinical trials, with 264 individuals, were included in qualitative analysis and eight articles with 184 individuals were included in the meta-analysis. There were significant effects on the fasting blood glucose (WMD: -2.75; 95% CI [-4.59; -0.90] mg/dL; p < 0.01; I2 = 88.7%; 7 studies) and HOMA-IR. (WMD: -0.50; 95% CI [-0.82; -0.19]; p < 0.01; I2 = 50.8%; 4 studies). The other outcomes were not significant. Three studies showed a high risk of bias. Seven outcomes were classified as very low quality and one as low quality. There was evidence of publication bias for fasting blood glucose. Conclusions: Although the eTRF regimen seems to have a beneficial effect on the fasting blood glucose and HOMA-IR of individuals with excess weight, the results of this meta-analysis should be analyzed with caution due to the low-quality evidence. ? 2020 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Automated summary

This meta-analysis aimed to evaluate the effect of early time-restricted feeding (eTRF) on the metabolic profile of adults with excess weight. The results showed potential benefits of eTRF on fasting blood glucose and HOMA-IR, although caution is needed due to the low-quality evidence.