Effects of time-restricted eating on metabolic panel and sleep profile in patients with type 2 diabetes: a...

Time-restricted eating (TRE), a novel dietary approach for the management of type 2 diabetes mellitus (T2DM), has been shown to affect the metabolic panel. Accordingly, this study aimed to evaluate the efficacy of the TRE on glycemic control, lipid profiles, anthropometric measurements, metabolic markers, and sleep-related outcomes in patients with T2DM.

A systematic search was conducted in PubMed, Embase, Web of Science, and the Cochrane Library from inception up to May 2026. A random-effects model was used, and effect sizes are reported with 95% confidence intervals (CIs). Because of substantial heterogeneity, pooled estimates are presented as hypothesis-generating rather than confirmatory.

Thirteen studies (n = 544 participants) were included from 915 records. The pooled analysis suggested that TRE may be associated with a reduction in glycemic control (HbA1c; WMD: -0.46%; 95% CI: -0.91, -0.00; p = 0.048) and in central adiposity (WC; SMD: -0.55; 95% CI: -1.09, -0.02; p = 0.042); however, these findings are based on low- to moderate-certainty evidence with very high heterogeneity (I ² > 90% for most outcomes). No significant effects were observed for fasting blood glucose (FBG), homeostatic model assessment for insulin resistance (HOMA-IR), lipid profile, blood pressure, dietary intakes, or sleep outcomes (p > 0.05). The reduction in body mass index (BMI) was not robust; it was entirely driven by a single study, as omitting this trial in the leave-one-out sensitivity analysis rendered the pooled estimate non-significant. Subgroup analyses based on duration, sample size, and age were underpowered and did not explain the heterogeneity. Quality assessment showed that most RCTs had a low risk of bias, but the GRADE certainty of evidence was downgraded to low or moderate for all outcomes, mainly due to serious inconsistency and imprecision.

TRE may offer a straightforward dietary approach that could have some benefits for glycemic control (HbA1c) and central adiposity (WC) in individuals with T2DM. However, due to substantial statistical heterogeneity, small sample sizes, the fragility of pooled estimates, and low-to-moderate GRADE certainty, the current evidence does not support a definitive clinical recommendation. For all other outcomes-weight, lipids, blood pressure, sleep, dietary composition, no consistent or robust evidence of an effect was found. High-quality, long-term RCTs are needed before firm conclusions can be drawn.