N/A
N=81
Pilot Study of Time Restricted Feeding as a Weight Loss Intervention
Obesity
Bottom Line
View on ClinicalTrials.gov: NCT03571048 ↗Enrolled (actual)
81
Serious AEs
0.0%
Results posted
Oct 2022
Primary outcome: Primary: Changes in Body Weight — -5.1; -6.2 kg
Study Design & Population
- Study type
- Interventional
- Phase
- N/A
- Interventions
- Reduced Calorie Diet (RCD) (Behavioral); Time Restricted Feeding (TRF) (Behavioral)
- Age
- Adult · 18+ yrs
- Sex
- All
- Sponsor
- University of Colorado, Denver
- Primary completion
- May 2020
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Changes in Body Weight |
-5.1; -6.2 | — |
| SECONDARY Changes in Fat Mass |
-2.1; -2.8 | — |
| SECONDARY Changes in Objectively Measured Energy Intake (Camera) |
-612.2; -647.3 | — |
| SECONDARY Changes in Physical Activity |
576; 596 | — |
| SECONDARY Changes in Sedentary Behavior |
-19.8; -0.77 | — |
Summary
The circadian timing of Energy Intake (EI) has emerged as a key factor in the regulation of body weight. Studies have suggested that eating later in the evening or at night when the circadian system is promoting sleep adversely influences weight loss. In contrast, restricting EI to a short window during waking hours and extending the length of the overnight fast (i.e., time restricted feeding, TRF) may be a practical and useful weight loss strategy. The overall objective of this proposal is to provide a foundation to inform the design of a future large-scale trial to evaluate the efficacy of TRF in generating weight loss. The investigators aims are to: 1) Assess processes critical for the success of a large-scale trial comparing the efficacy of a reduced calorie diet with time restricted feeding (RCD+TRF) versus standard RCD on weight loss; 2) Develop methodology to assess compliance to the RCD+TRF versus standard RCD program and collect preliminary data on whether the programs have differential effects on free-living behaviors (EI, appetite, physical activity, and sedentary behavior); and 3) Measure metabolic responses to RCD+TRF versus standard RCD to determine candidate mechanisms related to weight loss at 12wks and weight maintenance at 6mo post-intervention. The investigators primary hypothesis is that weight loss will be greater in the TRF group compared to the RCD group.
Eligibility Criteria
Inclusion Criteria
- Adult males and females with a BMI of 27-45 kg/m2 and weight stable over the previous 6 months;
- Age, 18-50 years old;
- Passing medical and physical screening, and analysis of blood and urine screening samples;
- Typical eating duration >12 hours per day (assessed by questionnaires);
- Own a smartphone
Exclusion Criteria
- Pregnancy or lactation for women (women who are >6 months postpartum with no plans of becoming pregnant in the next year and who are not currently lactating can be included; oral contraceptives will be allowed if medication has been consistent for the prior 6 months)
- Postmenopausal women (menopausal status will be assessed during the history and physical, with requirement of self-reported regular menstrual cycles for the last year; women who have undergone hysterectomy but with ovaries in place who continue to have regular menstrual symptoms can be included)
- Being considered unsafe to participate as determined by the study physician;
- History of cardiovascular disease, diabetes, uncontrolled hypertension, untreated thyroid, renal, hepatic diseases, dyslipidemia or any other medical condition affecting weight or lipid metabolism;
- History of human immunodeficiency virus or hepatitis B or C (self-report);
- Taking medications affecting weight or energy intake/energy expenditure in the last 6 months, including weight loss medications, antipsychotic drugs or other medications as determined by the study physician;
- Having abnormal blood chemistry (eGFR 3 times the upper limit of normal) or as deemed significant by the study physician;
- Being a smoker or having been a smoker in the 3 months prior to their screening visit;
- Working night shifts;
- Extreme early or extreme late chronotype as determined by the Munich Chronotype questionnaire37;
- Night eating syndrome (at least 25% of food intake is consumed after the evening meal and/or at least two episodes of nocturnal eating per week) as assessed with meal pattern assessment questionnaire;
- For participants completing the PSG studies, greater than moderate sleep apnea (score high risk ≥ 2 or more categories on the Berlin Questionnaire). Participants completing the primary weight loss intervention will not be excluded based on Berlin OSA risk scores.
- For participants completing the PSG studies, use of medications affecting sleep (benzodiazepines and other sleep aids, as determined by study physician). Participants completing the primary weight loss intervention will not be excluded based on use of medications affecting sleep.
Data sourced from ClinicalTrials.gov (NCT03571048). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.