Prolonged Daily Fasting as a Viable Alternative to Caloric Restriction in At-Risk Obese Humans

NCT04259632 | Completed Results

• 2 other identifiers: MED-2019-28331R01DK124484
• Study Type: interventional
• Target: 115
• Locations: 1 country
• Sites: 1

Brief Summary

Purpose: Obesity is reaching epidemic proportions, affecting 36% of the adult population in the United States. There is intense interest in dietary management to treat obesity and its associated complications. The first line of obesity treatment is caloric restriction (CR), although recidivism is common. For moderate CR, attrition rates of 20% are often reported, therefore weight loss options beyond CR are urgently needed.

Conditions

Obesity

Outcome Measures

Primary Outcomes (1)

• Change in Weight

  Weight will be measured by standard scale and reported in kilograms. This between 2 time points - baseline and 12 weeks

  12 weeks

Secondary Outcomes (6)

• Change in Whole Body Percent Fat

  Baseline, 12 weeks

• Change in Visceral Fat

  Baseline, 12 weeks

• Change in Lean Mass

  Baseline, 12 weeks

• Change in Fat Mass

  Baseline, 12 weeks

• Change in Caloric Intake

  Baseline, 12 weeks

Study Arms (3)

Time Restricted Eating (TRE)

EXPERIMENTAL

For the TRE group, we will restrict the eating window to 8 hours, where they will eat ad libitum. This is the same interval established by Dr. Panda and by our preliminary data. This interval will be entered into the mCC app and participants will be asked to adhere to this eating window during the intervention. All eating occasions will be logged using the mCC app. Only water and medications will be allowed outside of the eating window.

Behavioral: Time Restricted Eating (TRE)

Caloric Restriction (CR)

ACTIVE COMPARATOR

Participants randomized to CR will meet with the study dietitian prior to the intervention and be counseled on options to reduce their caloric intake by 15%, while maintaining their eating window. The 15% reduction was selected as our preliminary data and recent literature suggest that TRE with ad libitum intake reduces caloric intake by \~270 to 300 cal/day. The 15% CR is similar to the 11.9% CR achieved by the CALERIE-2 study, which is a 2 year study of CR.26 All eating occasions will be logged using the mCC app. The weekly dietitian review of the mCC information will include maintenance of the eating window and examination of dietary intake to determine compliance with the 15% CR.

Behavioral: Caloric Restriction (CR)

Unrestricted Eating (non-TRE)

NO INTERVENTION

For the unrestricted eating (non-TRE) group, participants will eat ad libitum per their usual habits. They will receive initial counseling about mCC logging. All eating occasions will be logged using the mCC app.

Interventions

Time Restricted Eating (TRE) BEHAVIORAL

daily eating window restricted to 8 hours

Time Restricted Eating (TRE)

Caloric Restriction (CR) BEHAVIORAL

15% daily caloric deficient

Caloric Restriction (CR)

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• BMI ≥30 and ≤ 55 kg/m\^2
• Own a smartphone compatible with the myCircadianClock (mCC) phone application
• Self-reported habitual wakening between 5-9 am
• Self reported sleep duration of 6-9 hours
• Weight must be stable \[+/- 5 pounds\] for at least 3 months prior to the study
• Eating window (time between 1st food intake and last food take) ≥14 hours using mCC
• Insulin resistance based on HOMA-IR≥ 2.5 from screening visit results
• Able to understand English

You may not qualify if:

• Use of beta-blockers or medications known to affect weight, such as thiazolidinedione (TZD), insulin, glucagon-like peptide (GLP)-1 agonists, phentermine, or sibutamine
• Shift work (i.e. working from 11pm to 7am)
• Clinically significant medical issues (diabetes, cardiovascular disease, uncontrolled pulmonary disease)
• A history of abnormal laboratory results, such as hematologic (platelets \< 100), hepatic (LFTs \> 2X nl), renal (Cr \> 1.5)
• MRI contraindication (metal in body, claustrophobia)
• Eating window \< 12 hours per day
• Unable to consistently document food intake using the mCC app (need at least 2 eating occasions\> 6 hours apart on a given day for at least 50% of days)
• Pregnancy
• Illiteracy
• Concern for active eating disorder per screening questionnaire
• Self-reported eating disorder or history of eating disorder

Sponsors & Collaborators

• University of Minnesota: lead
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

University of Minnesota

Minneapolis, Minnesota, 55455, United States

Location

Related Publications (1)

• Chen DA, Pena RH, Oldenburg N, Wang Q, Helgeson E, Yentzer B, Taddese A, LaPage N, Manoogian ENC, Panda S, Chow LS. Post-intervention sustainability of time-restricted eating versus caloric restriction: a secondary analysis. Int J Obes (Lond). 2026 Feb;50(2):474-477. doi: 10.1038/s41366-025-01968-2. Epub 2025 Nov 28.

  PMID: 41315749 DERIVED

MeSH Terms

Conditions

Obesity

Interventions

Caloric Restriction

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Diet Therapy; Nutrition Therapy; Therapeutics; Energy Intake; Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Results Point of Contact

• Title: Niki Oldenburg
• Organization: University of Minnesota

olden019@umn.edu

NA

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 4, 2020
• First Posted: February 6, 2020
• Study Start: October 15, 2020
• Primary Completion: October 12, 2023
• Study Completion: December 31, 2025
• Last Updated: January 23, 2026
• Results First Posted: February 24, 2025

Record last verified: 2026-01

Locations

US (1)