Time Restricted Feeding (4-hour Versus 6-hour) for Weight Loss in Obese Adults

• ClinicalTrials.gov Identifier: NCT03867773
• Recruitment Status: Completed
• First Posted: March 8, 2019
• Last Update Posted: June 24, 2022
• Sponsor: University of Illinois at Chicago
• Information provided by (Responsible Party): Krista Varady, University of Illinois at Chicago

Study Description

Brief Summary:

The aims of this proposal are to compare the effects of 4-h versus 6-h time restricted feeding (TRF) on body weight and metabolic disease risk factors in adults with obesity. To test the study objectives, a 10-week randomized, controlled, parallel-arm trial, divided into 2 consecutive periods: (1) 2-week baseline period; and (2) 8-week TRF weight loss period, will be implemented. Obese subjects will be randomized to 1 of 3 groups: (1) 4-h TRF, (2) 6-h TRF, or a no-intervention control group. This study will be the first randomized controlled trial to compare 4-h versus 6-h TRF.

Condition or disease	Intervention/treatment	Phase
Obesity; Diabetes	Behavioral: Time restricted feeding	Not Applicable

Detailed Description:

Modest weight loss of 5-10% is sufficient to reduce metabolic disease risk in obese individuals. The first line of therapy prescribed for weight loss is daily calorie restriction (CR; 25% restriction every day). However, adherence to CR greatly diminishes after 4-6 weeks, due to subject frustration with constantly having to count calories and never being able to eat freely. In light of these issues with CR, another approach that limits timing of food intake, instead of number of calories consumed, has been developed. This strategy is termed time restricted feeding (TRF), and involves confining the period of food intake to 8 h/d (10 am to 6 pm) without calorie counting. Preliminary findings of 8-h TRF demonstrate modest weight loss and blood pressure reductions after 12 weeks. What remains unknown however, is whether shorter feeding windows during TRF (such as 4-h or 6-h feeding windows) can produce even greater weight loss in obese adults. Also of interest, is the impact of these shorter feeding windows on metabolic disease risk indicators (such as plasma lipids, blood pressure, and insulin resistance, inflammation and oxidative stress). Accordingly, the aims of this proposal are: AIM 1: To compare the effects of 4-h versus 6-h time restricted feeding (TRF) on body weight in adults with obesity; AIM 2: To compare the effects of 4-h versus 6-h TRF on metabolic disease risk factors in adults with obesity. To test the study objectives, a 10-week randomized, controlled, parallel-arm trial, divided into 2 consecutive periods: (1) 2-week baseline period; and (2) 8-week TRF weight loss period, will be implemented. Obese subjects will be randomized to 1 of 3 groups: (1) 4-h TRF, (2) 6-h TRF, or a no-intervention control group. This study will be the first randomized controlled trial to compare 4-h versus 6-h TRF on body weight and metabolic disease risk markers.

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 82 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: None (Open Label)
• Primary Purpose: Prevention
• Official Title: Time Restricted Feeding (4-hour Versus 6-hour) for Weight Loss in Obese Adults
• Actual Study Start Date: February 1, 2019
• Actual Primary Completion Date: October 30, 2019
• Actual Study Completion Date: October 30, 2019

Arms and Interventions

Arm	Intervention/treatment
Experimental: 4-hour Time restricted feeding; 4-h TRF subjects will consume food ad libitum between 3pm and 7pm (4-h feeding window), and refrain from eating and drinking caloric beverages from 7pm to 3pm (20-h fasting window) each day. These subjects will not be instructed to limit/monitor energy intake during the feeding window. Subjects will be encouraged to drink plenty of water during the fasting period.	Behavioral: Time restricted feeding; TRF subjects will consume food ad libitum during the feeding window (4-h or 6-h window), and refrain from eating during the fasting window (20-h or 18-h window)
No Intervention: Control; Controls will be instructed to maintain their weight throughout the trial, and not to change eating or physical activity habits. Controls will visit the research center at the same frequency as the TRF groups (for outcome measurements).
Experimental: 6-hour Time restricted feeding; 6-h TRF subjects will consume food ad libitum between 1pm and 7pm (6-h feeding window), and refrain from eating and drinking caloric beverages from 7pm to 1pm (18-h fasting window) each day. These subjects will not be instructed to limit/monitor energy intake during the feeding window. Subjects will be encouraged to drink plenty of water during the fasting period.	Behavioral: Time restricted feeding; TRF subjects will consume food ad libitum during the feeding window (4-h or 6-h window), and refrain from eating during the fasting window (20-h or 18-h window)

Outcome Measures

Primary Outcome Measures :

1. Change from baseline to week 8 in body weight [ Time Frame: Measured at week 1 and 8 ]
   Measured by an electronic scale

Secondary Outcome Measures :

1. Change from baseline to week 8 in body composition [ Time Frame: Measured at week 1 and 8 ]
   Measured by DXA
2. Change from baseline to week 8 in Insulin resistance [ Time Frame: Measured at week 1 and 8 ]
   Measured as HOMA-IR
3. Change from baseline to week 8 in Fasting glucose [ Time Frame: Measured at week 1 and 8 ]
   Measured with a hexokinase reagent kit
4. Change from baseline to week 8 in Fasting insulin [ Time Frame: Measured at week 1 and 8 ]
   Measured as total immunoreactive insulin
5. Change from baseline to week 8 in Blood pressure [ Time Frame: Measured at week 1 and 8 ]
   Measured by a blood pressure cuff
6. Change from baseline to week 8 in adverse events [ Time Frame: Measured weekly from baseline to week 8 ]
   Measured by questionnaire
7. Change from baseline to week 8 in plasma lipids [ Time Frame: Measured at week 1 and 8 ]
   Measured by outside lab (Medstart, IN)
8. Change from baseline to week 8 in heart rate [ Time Frame: Measured at week 1 and 8 ]
   Measured by a blood pressure cuff
9. Change from baseline to week 8 in inflammatory markers (TNF-a, IL-6) [ Time Frame: Measured at week 1 and 8 ]
   Measured by ELISA
10. Change from baseline to week 8 in oxidative stress (8-isoprostane) [ Time Frame: Measured at week 1 and 8 ]
    Measured by ELISA
11. Change from baseline to week 8 in calorie and macronutrient intake [ Time Frame: Measured at week 1 and 8 ]
    Measured by food record
12. Change from baseline to week 8 in physical activity (steps/d) [ Time Frame: Measured at week 1 and 8 ]
    Measured by activity monitor
13. Change from baseline to week 8 in diet adherence [ Time Frame: Measured weekly from baseline to week 8 ]
    Measured by a questionnaire
14. Change from baseline to week 8 in sleep quality [ Time Frame: Measured at week 1 and 8 ]
    Measured by a questionnaire
15. Change from baseline to week 8 in insomnia severity [ Time Frame: Measured at week 1 and 8 ]
    Measured by a questionnaire
16. Change from baseline to week 8 in risk of sleep apnea [ Time Frame: Measured at week 1 and 8 ]
    Measured by a questionnaire
17. Change from baseline to week 8 in sex steroid levels (estrogen, androgens, sex hormone binding globulin) [ Time Frame: Measured at week 1 and 8 ]
    Measured by a ELISA

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 65 Years (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

• Male or female;
• body mass index (BMI) between 30.0 and 49.9 kg/m2;
• age between 18 and 65 years; sedentary (light exercise less than 1 h per week) or moderately active (moderate exercise 1 to 2 h per week);
• weight stable for >3 months prior to the beginning of the study (gain or loss <4 kg);
• able to give written informed consent

Exclusion Criteria:

• Smoker; diabetic;
• taking weight loss medications;
• taking medication that requires eating food before (or with) the medication; history of eating disorders;
• night-shift workers;
• perimenopausal;
• pregnant women

Contacts and Locations

Locations

United States, Illinois

University of Illinois Chicago

Chicago, Illinois, United States, 60612

Sponsors and Collaborators

University of Illinois at Chicago

More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

Cienfuegos S, Gabel K, Kalam F, Ezpeleta M, Lin S, Varady KA. Changes in body weight and metabolic risk during time restricted feeding in premenopausal versus postmenopausal women. Exp Gerontol. 2021 Oct 15;154:111545. doi: 10.1016/j.exger.2021.111545. Epub 2021 Aug 31.

Cienfuegos S, Gabel K, Kalam F, Ezpeleta M, Wiseman E, Pavlou V, Lin S, Oliveira ML, Varady KA. Effects of 4- and 6-h Time-Restricted Feeding on Weight and Cardiometabolic Health: A Randomized Controlled Trial in Adults with Obesity. Cell Metab. 2020 Sep 1;32(3):366-378.e3. doi: 10.1016/j.cmet.2020.06.018. Epub 2020 Jul 15.

• Responsible Party: Krista Varady, Professor of Nutrition, University of Illinois at Chicago
• ClinicalTrials.gov Identifier: NCT03867773
• Other Study ID Numbers: 2018-1525
• First Posted: March 8, 2019
• Last Update Posted: June 24, 2022
• Last Verified: June 2022

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No

Additional relevant MeSH terms:

Weight Loss; Body Weight Changes; Body Weight