Table 2.
Major findings of time-restricted eating trials in humans with metabolic syndrome or its components.
| Reference and Study Design | MetS Components | Results of TRE |
|---|---|---|
| Gill and Panda [10] One group (pre-post design), pilot feasibility study |
Mean BMI > 30 kg/m2 | ↓ Body weight ↓ Hunger at night ↑ Morning and overall energy levels and sleep satisfaction ↓ Energy intake |
| Antoni et al. [34] Randomized controlled trial, pilot feasibility study |
BMI 29 ± 2 kg/m2 | ↔ Body weight ↓ Body fat ↓ FPG ↔ Fasting insulin, lipids ↓ Energy intake ↓ EW by ~4.5 h |
| Sutton et al. [35] Crossover |
BMI 32 ± 4 kg/m2 FPG 102 ± 9 mg/dL |
↔ Body weight ↑ Insulin sensitivity, β-cell function, TG ↔ FPG, lipids, TNF-α, IL-6 ↓ BP, fasting and postprandial insulin, evening appetite, oxidative stress Adherence to TRE was 98% (rigorously controlled trial) |
| Gabel et al. [36,106,107] Matched historical controls, pilot study |
BMI ≥ 30 kg/m2 HDL-C 48 ± 2 mg/dL |
↓ Body weight ↔ Body fat, FPG, fasting insulin, insulin resistance, lipids, homocysteine, sleep quality/duration ↓ Energy intake ↓ Systolic BP |
| Hutchison et al. [37] Crossover |
WC 115 ± 2 cm BP 141 ± 3/87 ± 2 mmHg FPG 105 ± 2 mg/dL |
↓ Body weight ↔ Body fat, FPG ↓ Mean fasting glucose (CGM) in eTRE ↑ Glucose tolerance ↓ Fasting TG, hunger |
| Anton et al. [38] One group (pre-post design), pilot feasibility study |
WC 109 ± 13 cm BP 146 ± 16/78 ± 12 mmHg FPG 106 ± 28 mg/dL BMI 34 ± 3 kg/m2 |
↓ Body weight ↔ Blood glucose, WC, physical and cognitive function ↑ Quality of life Adherence to TRE was 84% |
| Jamshed et al. [39] Ravussin et al. [40] Crossover |
BMI 30 ± 3 kg/m2 | ↓ Mean 24 h glucose and glycemic excursions (CGM) ↓ Morning FPG, insulin and HOMA-IR; mean and morning ghrelin, mean appetite ↑ Morning ketones, TC, LDL-C and HDL-C; metabolic flexibility, fullness, fat oxidation ↔ Energy expenditure Altered cortisol patterns and circadian clock genes expression related to aging, stress, autophagy, oxidative stress |
| Kesztyüs et al. [41] One group (pre-post design), pilot feasibility study |
WC 107 ± 13 cm | ↓ Body weight ↓ WC ↓ HbA1c ↔ Lipids Adherence to TRE was 86% |
| Wilkinson et al. [16] One group (pre-post design), pilot study |
Diagnosed MetS WC 109 ± 11 cm FPG 107 ± 15 mg/dL TG 161 ± 87 mg/dL HDL-C 47 ± 13 mg/dL BMI 30 ± 5 kg/m2 |
↓ Body weight ↓ WC ↓ Body fat ↔ Mean glucose (CGM), FPG, fasting insulin, HOMA-IR, HbA1c, HDL-C, TG, sleep quality ↓ TC, LDL-C, non-HDL-C ↓ Energy intake ↓ BP |
| Chow et al. [11] Randomized controlled trial, feasibility study |
BMI 34 ± 8 kg/m2 BP 132 ± 13/85 ± 4 mmHg |
↓ Body weight ↓ Visceral fat mass, lean mass ↓ Fasting glucose (CGM), TG ↔ Mean glucose (CGM), glucose tolerance, HbA1c, lipids No significant differences in changes of fasting glucose and TG between TRE and non-TRE groups |
| Cienfuegos et al. [42] Randomized controlled trial |
BMI 36 ± 1 kg/m2 BP 135 ± 5/88 ± 2 mmHg |
↓ Body weight ↓ Fat mass ↓ Energy intake ↓ Insulin resistance ↓ Oxidative stress ↔ TNF-α, IL-6 |
| Parr et al. [43] Randomized controlled crossover trial |
BMI 32 ± 2 kg/m2 | ↔ Peak and waking glucose, AUC 24 h glucose (CGM) and insulin ↓ AUC nocturnal glucose (CGM) ↑ Feeling of well-being, TG |
| Lowe [44] Randomized controlled trial |
BMI 31 ± 5 kg/m2 | ↓ Body weight, lean mass, energy expenditure, diastolic BP ↔ Fat mass, FPG, fasting insulin, HOMA-IR, HbA1c, lipids, systolic BP No significant differences in changes of outcomes between TRE and non-TRE groups |
Abbreviations: AUC: area under the curve; BMI: body mass index; BP: blood pressure; CGM: continuous glucose monitor; dTRE: delayed-time-restricted eating; eTRE: early-time-restricted eating; EW: eating window; HbA1c: glycated hemoglobin; HDL-C: high-density lipoprotein cholesterol; HOMA-IR: homeostatic model assessment for insulin resistance; IL-6: interleukin-6; LDL-C: low-density lipoprotein cholesterol; MetS: metabolic syndrome; OGTT: Oral Glucose Tolerance Test; T2DM: type 2 diabetes mellitus; TC: total cholesterol; TG: triglycerides; TNF-α: tumor necrosis factor-α; TRE: time-restricted eating; WC: waist circumference; ↑: increased levels; ↓: decreased levels; ↔: no difference.