Health effects of the time-restricted eating in adults with obesity: A systematic review and meta-analysis

Abstract

BackgroundThe number of people suffering from overweight or obesity has been steadily increasing in recent years. As a new form of diet, the efficacy of time-restricted eating (TRE) remains debatable.ObjectiveThis meta-analysis quantified the effect of TRE on weight change and other physical parameters in obese and overweight adults.MethodsWe did a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the TRE interventions on weight loss and other metabolic parameters by searching PubMed, Embase, and Cochrane Central Register of Controlled Trials to identify eligible trials published from database inception up until 23 August 2022. The risk of bias was assessed using the Revised Cochrane risk-of-bias tool (ROB-2.0). Meta-analysis was performed using Review Manager 5.4.1 software.ResultsNine RCTs with 665 individuals (345 in the TRE group while 320 in the control group) were included. Results indicated that TRE had a greater decrease in body weight (−1.28 kg; 95% CI [−2.05, −0.52], p = 0.001), fat mass (−0.72 kg; 95% CI [−1.40, −0.03], p = 0.04), body mass index (−0.34 kg/m2; 95% CI [−0.64, −0.04], p = 0.03) and diastolic blood pressure (−2.26 mmHg 95% CI [−4.02, −0.50], p = 0.01). However, the meta-analysis demonstrated that there was no significant difference between TRE and the control group in lean mass, systolic blood pressure, waist circumference, fasting glucose, fasting insulin, homeostasis model assessment-insulin resistance (HOMA-IR), total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides. Besides, the duration of the study and daily eating window also had an impact on weight change.ConclusionTRE was associated with reductions in weight and fat mass and can be a dietary intervention option for adults with obesity. But high-quality trials and longer follow-ups are needed to draw definitive conclusions.

Time-restricted eating improves health because of energy deficit and circadian rhythm: A systematic review and meta-analysis

“…However, the intervention effect of TRE in health improvement was greatest in the e-TRE subgroup with considerable energy deficit. The relatively modest magnitude has been demonstrated in some previous meta-analysis, some attributed this to the short intervention duration 45 while other did not find the association between health improvement and duration. 34 Thus, more long-term TRE studies are needed to get a more solid conclusion, both in people with overweight or obesity status and patients with metabolic symptoms.…”

“…This modest reduction was in line with previous meta-analysis so we further do meta-regression to explore the mechanism of weight loss in TRE strategies. 34 , 35 , 36 , 45 Meta-regression showed that weight loss was significantly related to energy consumption ( Z = 5.23, p < 0.001) and the eating window ( Z = 2.26, p = 0.024) but was not correlated with the intervention duration ( Z = 0.36, p = 0.72). This demonstrated an increased capacity for TRE to cause weight loss by a greater calorie deficit and shorter eating window within a safe range.…”

“…This meta-analysis found decreased systolic blood pressure in the TRE group under the ad libitum intake condition with sizable energy reduction, whereas diastolic blood pressure remained the same, consistent with another recently published meta-analysis. 45 , 54 A study in shift workers found a significant decrease in blood pressure among participants with elevated systolic blood pressure (≥130 mmHg) or diastolic blood pressure (≥85 mmHg) compared to those with normal initial levels, indicating the salience of TRE in people with elevated cardiometabolic risks at baseline. 55 In addition, subgroup analysis showed that systolic blood pressure was decreased under the ad libitum condition and that e-TRE was more effective compared to d-TRE only with relatively lower energy intake.…”

Real‐world data of a digitally enabled, time‐restricted eating weight management program in public sector workers living with overweight and obesity in the United Kingdom: A service evaluation of the Roczen program

“…TRE is a form of intermittent fasting involving a period of fasting and eating within each 24‐h period for example, 16:8 (16 h fasting and 8 h eating) 20 . Substantial evidence exists supporting the effectiveness of TRE in achieving substantial weight loss, cardiometabolic health, and mental health 21,22 . Despite this, there remains limited evidence evaluating a digital TRE program in patients living with overweight and obesity, particularly in the real world and in a workplace setting.…”

The Effect of Intermittent Fasting on Appetite: A Systematic Review and Meta-Analysis

“…The 5:2 diet involves limiting energy intake to 500 calories in women and 600 calories in men, for two non-consecutive days per week, with unrestricted eating for the rest of the week [13]. TRE is slightly different, as it involves following the same routine every day, where you eat within a certain window of hours and fast in the remaining hours [14], for example, the 16:8 diet, where eating is only allowed within an 8 h window each day [15].…”