Table 1.

Clinical trials on TRE with outcomes regarding glucose and lipid metabolism.

Reference	Cohort (Male/Female)	Study design TRE Regimen(Fasting: Feeding)	Study duration	Calorie intake/weight change	Glucose metabolism	Lipid metabolism	Other effects
Antoni et al. 2018 (62)	n = 13 (1/12) healthy adults age: 29-57 years	non-randomized controlled trial parallel armTRE: daily feeding duration shortened by 3 h	12 weeks: 2 weeks baseline10 weeks intervention	− Ad libitum food access↓ daily energy intake ↔ distribution of macronutrients− ns body weight loss	↓ fasting glucose (primarily driven by an increase among controls)	− ns reduction in LDL and increase in HDL	↓ body fat mass
Cai et al., 2019 (63)	n = 174 (52/122) NAFLD patients age: 34,1 ± 6,6 years	RCT parallel arm TRE (16: 8) self-selected feeding window	12 weeks intervention	− Ad libitum food access− provided with a meal per day↔ energy intake↓ body weight	↔ fasting glucose and insulin	↓ serum TG↔LDL, HDL, and total cholesterol	↓ fat mass
Chow et al. 2020 (64)	n = 20 (3/17) overweight adults with a prolonged eating window >15 h/day age: 45,5 ± 12,1 years	RCT parallel arm TRE (13-16: 8-11) self-selected hour window	~16 weeks: ~ 4 weeks preintervention12 weeks intervention	− ad libitum food intake− no measure of caloric intake (or not published) ↓ body weight	vs. preintervention↓ fasting glucose↑ time blood glucose levels within target (70-180 mg/dL) (CGM measure)	vs. preintervention↓ TG↔ LDL, HDL	↔ physical activity↓ number of eating occasions(a) vs. non-TRE group↓ visceral fat↓ lean mass(b) vs. preintervention↓ fat mass ↓ lean mass↓ visceral fat
Cienfuegos et al., 2020 (65)	n = 49 (5/44) obese adults age: 47 ± 2 years	RCT parallel arm (a) lTRE (18: 6) 1 pm–7 pm.(b) lTRE (20: 4) 3 pm to 7 pm	10 weeks: 2 weeks baseline8 weeks intervention	− ad libitum food intake↓ energy intake ~550 kcal/day↓ body weight	↔ fasting glucose↓ fasting insulin↓ insulin resistance(partly driven by a worsening in control group)	↔ TG, HDL, and LDL	↓ fat mass↓ lean mass with (18: 6) vs. control and vs. (20: 4) ↓ 8-isoprostane
Gabel et al., 2018 (66) Gabel et al., 2020 (67)	n = 23 (3/20) obese adults age: 50 ± 2 years	historically controlled study TRE (16: 8) 10 am–6 pm	14 weeks: 2 weeks baseline12 weeks intervention	− ad libitum food intake↓ caloric intake~ 350 kcal/day↔ macronutrients↓ body weight	↔ glucose, insulin, HOMAR-IR	↔ TG, HDL, and LDL	↓ systolic blood pressure ↔ physical activity↔ gut microbiome
Hutchison et al., 2019 (68)	n = 15 (15/0) prediabetic men age: 55 ± 3 years	RCT crossover design (a) eTRE (15: 9) 8 am to 5 pm (b) lTRE (15: 9) 12 pm–9 pm	5 weeks: 1 week baseline 1 week each intervention 2 weeks washout	− ad libitum food intake− no measure of caloric intake (or not published) ↓ body weight	↓ glucose iAUC↔ fasting glucose and insulin↓ mean fasting glucose in eTRE (CGM data)	↓ fasting TG↔ NEFA	↔ physical activity ↔ gastrointestinal hormones ↔ perceived hunger, fullness, desire to eat
Jamshed et al., 2019 (69) Ravussin et al., 2019 (70)	n = 11 (7/4) overweight adults age: 32 ± 7 years	RCT crossover design eTRE (18: 6) 8 am–2 pm	~5-6 weeks: 4 days each intervention 3,5-5 weeks washout	− isocaloric controlled feeding approach− days 1-2: participants followed eating schedule on their own− days 3-4: standardized meals eaten under supervision↔ weight between arms before respiratory chamber↓ body weight while respiratory chamber day in eTRE vs. controls	↓ mean 24-h glucose ↓ glycemic excursions (M age) ↓ morning fasting glucose, insulin, and HOMA-IR ↑ evening insulin and HOMA-IR↔ evening glucose	↑ morning total cholesterol, HDL, LDL↔ morning TG, free fatty acids↔ evening lipid levels	↔ 24 h energy expenditure ↓ mean ghrelin↓ morning levels of ghrelin, leptin, GLP-1↑ PYY in evening↑ metabolic flexibility ↑ ketones in morning↓ evening cortisol
Jones et al. 2020 (71)	n = 16 (16/0) healthy men age: 23 ± years	Non-randomized trial Two groups recruited & tested temporally apart(a) eTRE (16: 8) 8 am–4 pm(b) energy-matched control/caloric restriction intervention (CON : CR)	3 weeks: 1 week baseline 2 weeks intervention	− ad libitum food intake in eTRE group− prescribed dietary plans and all dietary intakes provided in CON : CR group to match eTRE↓ caloric intake~ 400 kcal/day↓ body weight (matched in Con : CR)	↑ whole-body insulin sensitivity↑ glucose uptake of skeletal muscle↔ mean 24-h glucose↔ fasting insulin	↔ serum TG	↔ physical activity↑ fasting ghrelin
Karras et al., 2020 (72)	ntotal = 60 (17/43) orthodox fasting n=37 (11/26) TRE n=23 (6/17) overweight, metabolically healthy adults age: 48.3 ± 8.9 years	non-randomized, parallel arm trial(a) orthodox fasting (b) eTRE (16: 8) 8 am–4 pm	12 weeks: 7 weeks intervention follow up 5 weeks after intervention	(a)  hypocaloric dietary plans based on orthodox fasting: no animal products, except for 2 days fish (b)  hypocaloric dietary plans with two meals (8 am and 1 pm) and two snacks (11 am and 3: 30 pm) ↔ caloric intake↓ body weight (both groups vs. pre-intervention)	↔ fasting glucose, fasting insulin↔ insulin resistance (HOMA-IR) and ß-cell function	↔ total cholesterol, LDL↑ TG↓ HDL	vs. orthodox fasting: ↓ waist circumferencevs. pre-intervention: ↓ waist circumference↓ body fat↔ C-reactive protein
Kesztyüs et al., 2019 (73)	n = 40 (9/31) abdominally obese adults age: 49,1 ± 12,4 years	single arm trial TRE (15-16: 8-9) self-selected hour window	12 weeks intervention	− ad libitum food intake− no measure of caloric intake↓ body weight	↓ HbA1c	↔ total cholesterol, HDL, LDL, TG	↓ waist circumference
Li et al., 2021 (74)	n = 15 (0/15) women with anovulation and PCOS age: between 18 and 31 years	single arm triale TRE (16: 8) 8 am–4 pm	6 weeks: 1 week baseline 5 weeks intervention	− isocaloric approach (fluctuations for no more than 10% from baseline caloric intake) ↓ body weight	↔ fasting glucose, glucose AUC↓ fasting insulin, insulin AUC↓HOMA-IR, AUCInsulin/AUCGlucose	↔ total cholesterol, LDL, TG	↓ body fat↓ visceral fat↓ C-reactive protein and alanine aminotransferase↑ IGF-1
Lowe et al. 2020 (75)	ntotal = 116 (70/46) in-person tested: n = 50 (28/22) overweight, obese adults age: 46,5 ± 10,5 years	RCT parallel arml TRE (16: 8) 12 pm–8 pm	12 weeks intervention	− ad libitum food intake− no measure of caloric intake↓ body weight (vs. baseline ns from control group)	↔ fasting glucose, fasting insulin, HOMA-IR, HbA1c	↔ total cholesterol, HLD, LDL, TG	↓ appendicular lean mass
Martens et al., 2020 (76)	n = 22 (10/12) healthy, non-obese adults age: 67 ± 1 years	RCT crossover design lTRE (16: 8) consistent self-selected hour window starting between 10 and 11 am	7 weeks: 1 week baseline 6 weeks each intervention	− ad libitum food intake↔ total energy intake↔ diet composition (healthy eating index) ↔ body weight	↔ fasting glucose↓ glucose AUC (during OGTT) ↔ plasma insulin	↑ total cholesterol and LDL	↔ total body composition ↔ bone density↓ sensation of hunger
McAllister et al., 2019 (77)	n = 22 (22/0) physically active men age: 22 ± 2,5 years	randomized two parallel arm trial (a) ad libitum TRE (16: 8) (b) isocaloric TRE (16: 8) self-selected hour window	4 weeks intervention	(a) ad libitum food intake (b) isocaloric food intake = advised to eat <± 300 kcal from baseline measured caloric intakein both groups: − ns lower caloric intake↓ body weight	↔ blood glucose↔ plasma insulin	↑ HDL↔ mean TG	↓ body fat↓ blood pressure ↑ adiponectin
Moro et al., 2016 (78)	n = 34 (34/0) healthy resistance trained men age: 29,21 ± 3,8 years	RCT parallel arm (a) lTRE (16: 8) 1 pm–9 pm+ RT (b) control eating window: 8 am–9 pm + RT	8 weeks intervention	− caloric intake consumed in 3 meals per day at standardized times within 1 h↔ caloric intake and macronutrient distribution↓ body weight	TRE pre vs. post (not control) : ↓ blood glucose ↓ insulin andHOMA-IR	↓ TG↔ total cholesterol, LDL, HDL	↓ fat mass↔ lean mass ↓ testosterone↓ IGF-1 ↑ adiponectin↓TNF-α, IL-1β ↓ respiratory ratio
Parr et al. 2020 (79)	n = 19 (9/10) adults with T2D and eating window >12 h/day age: 50 ± 9 years	single arm trial TRE (15: 9) 10 am–7 pm	6 weeks: 2 weeks baseline4 weeks intervention	− ad libitum food intake↔ caloric intake and macronutrient distribution↔ body weight	↔ fasting glucose, insulin ↔ glucose and insulin AUC ↔ HbA1c	↔ total cholesterol, HDL, LDL, TG	↑ adherence to TRE reduced energy intake ↔ psychological well-being
Parr et al., 2020 (80) Lundell et al. 2020 (81)	n = 11 (11/0) sedentary men with overweight/obesity age: 38 ± 5 years	RCT crossover design (a) TRE (16: 8) 10 am–6 pm (b) extended feeding of 15 h/day7 am–10 pm	3 weeks: 5 days each intervention 10 days washout	− isocaloric feeding, meals provided and consumed at standardized times within ± 30 min− no measure of weight loss	↓ nocturnal glucose AUC ↔ waking glucose AUC ↔ peak glucose↔ 24-h and peak glucose (CGM) ↔ peak insulin− ns tendency to ↓ AUC total insulin	↔ TG AUC total↑ peak TG↑ AUC total and peak NEFA	↓ C-Peptide AUC total↔ physical activity↓ evening hunger ↔ muscle core clock gene expression− alters rhythmicity of serum and muscle metabolites and amino acid transport
Peeke et al., 2021 (82)	n = 60 (7/53) obese adults age: 44 ± 11 years	RCT parallel arm, virtual trial (a)  control: (12: 12) (b) TRE: (14: 10) with fasting snack after 12 h on 5 days/weekin both groups fasting period began after dinner between 5 pm and 8 pm	8 weeks intervention	− Hypocaloric dietary regimes based on Jenny Craig® Rapid Results program− 3 meals and 1 snack provided per day↓ body weight	↓ fasting plasma glucose	n/a	Fasting snack decreased hunger
Phillips et al., 2021 (83)	n = 45control n=20adults with eating windows ≥14 h/day and at least one metabolic syndrome component age: 43.4 ± 13.3 years	RCT parallel arm TRE (12: 12) self-selected hour window	7 months: 4 weeks baseline6 months intervention	− ad libitum food intake− no quantitative measure of caloric intake↓ body weight	↔ fasting glucose, HbA1c	↔ HDL cholesterol, TG	↓ waist circumference
Sutton et al. 2018 (84)	n = 8 (8/0) overweight men with prediabetes age: 56 ± 9 years	RCT crossover design eTRE (18: 6) dinner before 3 pm	17 weeks: 5 weeks each intervention7 weeks washout	− isocaloric controlled feeding approach with standardized meals eaten under supervision− ns weight loss	↓ insulin (fasting, mean and peak) ↑ insulin sensitivity↑ß-cell responsiveness↓ insulin resistance	↑ fasting TG↔ HDL and LDL cholesterol	↓blood pressure↓desire to eat in the evening↓8-isoprostane↓fasting PYY
Tinsley et al. 2019 (85)	ITT: n = 40 (0/40) PP: n = 24 (0/24) healthy resistance trained females age: 22,1 ± 2,6 years	RCT parallel arm (a) lTRE (16: 8) 12 pm–8 pm + placebo +RT(b)  lTRE (16: 8) 12 pm–8 pm + 3 mg/day HMB + RT(c) ND + placebo + RT	8 weeks intervention	− ad libitum food intake+ provided supplemental whey protein↔ caloric intake (increase in all groups due to provided protein supplements) ↓ body weight	↔ fasting glucose, insulin	↔ total cholesterol, HLD, LDL, TG	↔ muscular improvements↓ fat mass in PP analysis in lTRE groups
Wilkinson et al., 2020 (86)	n = 19 (13/6) adults with metabolic syndrome and eating window ≥14 h/day age: 59 ± 11 years	single arm trial TRE (14: 10) consistent self-selected hour window	14 weeks: 2 weeks baseline12 weeks intervention	− ad libitum food intake↓ caloric intake↓ body weight	ns trend towards↓ fasting glucose, fasting insulin, and HbA1c↓ HbA1c in participants with elevated fasting glucose and HbA1c at baseline	↓ total cholesterol, LDL, and non-HDL↔ TGns tendency to lower HDL	↓ body fat↓ visceral fat↓ waist circumference↓ blood pressure ↑ restfulness↔ physical activity
Zeb et al., 2020 (87)	n = 80 (80/0) control n=24young aged healthy men age: n/a	RCT parallel arml TRE (16: 8) 7: 30 pm–3: 30 am	25 days intervention	− ad libitum food intake↓ caloric intake↔ body weight	n/a	↓ total cholesterol and TG↔ LDL ↑ HDL (in both: pre- vs. post-intervention and vs. control)	↑ liver function↑ gut microbial diversity↑ circadian gene expression (Bmal1, Clock, Sirt1)

Studies investigated effects of a single meal consumed at different times of the day are not included in the table. ↑, increase; ↓, decrease; ↔, no significant change. AUC_total, total 24-h area under the curve; CGM, continuous glucose monitoring; CON, CR, control/caloric restriction intervention; eTRE, early time-restricted eating; EXF, extended feeding; HbA1c, glycated hemoglobin A1c; HDL, high density lipoprotein; HMB, β-hydroxy β-methylbutyrate; HOMA-IR, homeostatic model assessment of insulin resistance; iAUC, incremental area under the curve; ITT, intention to treat; LDL, low density lipoprotein; lTRE, late time-restricted eating; MAGE, mean amplitude of glycemic excursions; ND, normal diet; NEFA, nonesterified fatty acids; ns, non-significant modification (p > 0,05); OGTT, oral glucose tolerance test; PCOS, polycystic ovary syndrome; PP, per protocol; PYY, peptide YY; RCT, randomized controlled trial; RT, resistance training; T2D, type 2 diabetes; TG, triglycerides; TRE, time-restricted eating; n/a, not available.