TABLE 1.

The characteristics of studies.

Study, year	N	Design	TRE Window	Methods of tracking TRE	Type of patients
Arnason and Kerry (19)	10	Three-phase observational study (2-week baseline, 2-week intervention, 2-week follow up)	4–6 h eating window; 2 weeks	Self-reporting; remote food photography for a random 3-day food diary	T2DM (fasting glucose > 7.0 mmol, HbA1c > 6.5%, or OGTT > 11.0 mmol)
Andriessen et al. (12)	14	Randomized crossover trial	within a 10 h window no later than 18:00 h 10 weeks	A weekly phone call	T2DM, BMI > 25 kg/m
Chair et al. (15)	101	RCT (randomized into the ADF group, 18/8 TRF group, and control group)	8-h TRE; 3 weeks	Individualized menus and counseling; weekly telephone calls from nurse	Prediabetes
Che et al. (11)	120	RCT (TRE and control group)	10-h TRE (8 a.m.–6 p.m.); 12 weeks	A daily log was used to record	T2DM
Kahleova et al. (16)	54	RCT (randomized, open, crossover, single-center study)	breakfast (6–10 a.m.); lunch (12:00–4 p.m.) 12 weeks	All the meals were provided for one half of the participants; dietary record	T2DM
Parr et al. (17)	19	The non-randomized study	9 h TRE (10 a.m.–7 p.m.), 4 weeks	Written food diary or smartphone app to record all food entries. Photos of each food/beverage also taken using phone	T2DM (HbA1c > 6.5 and < 9%) and eating window > 12 h
Sutton et al. (18)	8	Randomized crossover trial	6 h TRE (no later than 14;00 h), 5 weeks	All meals provided and consumed under supervision	Prediabetes

TRE, Time-restricted eating; TRF, Time-restricted feeding; BMI, Body Mass Index; ADF, Alternate-day Fasting; T2DM, Diabetes Mellitus type 2; HbA1c, Glycosylated Hemoglobin, Type A1c; OGTT, Oral Glucose Tolerance Test; RCT, Randomized Clinical Trial.